RESEARCH Open Access

User-centred participatory design of visualcues for isolation precautionsLauren Clack1 Manuel Stuumlhlinger2 Marie-Theres Meier1 Aline Wolfensberger1 and Hugo Sax1

Abstract

Background Isolation precautions are intended to prevent transmission of infectious agents yet healthcareprovider (HCP) adherence remains suboptimal This may be due to ambiguity regarding the required precautions orto cognitive overload of HCPs In response to the challenge of changing HCP behaviour increasing attentionshould be paid to the role of engineering controls and facility design that incorporate human factors elements Inthe current study we aimed to develop an isolation precaution signage system that provides visual cues serves asa cognitive aid at the point of care and removes ambiguity regarding which precautions are necessary (eg masksgowns gloves single rooms) when caring for isolated patients

Methods We employed a user-centred participatory design approach in which HCPs were actively involved ingenerating an isolation precaution signage system based on human factors design principles HCPs werepurposefully sampled for each design phase to include a representative sample of potential system users Weconducted front-end analysis through interviews and observations to identify challenges related to the existingsignage and to establish design requirements for new signage This was followed by the creation of user personasdesign thinking workshops and prototyping which then underwent iterative cycles of evaluation Graphicalsymbols were developed and tested for comprehensibility

Results Front-end analysis revealed several barriers to use of the current signage system such as unclear targetaudience low signal-to-noise ratio and ambiguity regarding the applicable precautions A comprehensive list ofdesign requirements was generated The project ultimately resulted in a collection of validated comprehensiblesymbols and signs for contact droplet and airborne isolation as well as the identification of several systems-levelsolutions for work re-organisation to improve compliance with isolation precautions

Conclusions The introduction of visual cues in the form of signage offers a promising opportunity to makeguidelines available directly at the frontline Anecdotal evidence based on observations and interviews with HCPhave shown that the current solution is superior to previous isolation signage User-centred participatory designwas a useful approach that holds potential for further improving design in healthcare settings

Keywords Infection control Isolation precautions Personal protective equipment Human factors User-centreddesign Participatory design Co-design Visual cues Signage

IntroductionHealthcare-associated infections (HAI) are a major threatto patient safety on a global level even in high-incomecountries [1] Adherence to recommended infection controlpractices such as outlined by the Centers for DiseaseControl (CDC) recommendations on isolation precautions

decreases transmission of infectious agents in healthcaresettings significantly reducing the burden of HAI [2]Transmission-based precautions are designed to preventcontact droplet or airborne transmission of infectiousagents from a source to a susceptible host In spite of thedemonstrated effectiveness of such measures to preventtransmission healthcare provider (HCP) compliancehas been shown by observational studies to be sub-optimal with adherence to isolation and universal

copy The Author(s) 2019 Open Access This article is distributed under the terms of the Creative Commons Attribution 40International License (httpcreativecommonsorglicensesby40) which permits unrestricted use distribution andreproduction in any medium provided you give appropriate credit to the original author(s) and the source provide a link tothe Creative Commons license and indicate if changes were made The Creative Commons Public Domain Dedication waiver(httpcreativecommonsorgpublicdomainzero10) applies to the data made available in this article unless otherwise stated

Correspondence Laurenclackuszch1Division of Infectious Diseases and Hospital Epidemiology UniversityHospital Zurich and University of Zurich Raemistrasse 100 HAL14 8091Zurich SwitzerlandFull list of author information is available at the end of the article

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 httpsdoiorg101186s13756-019-0629-9

precautions ranging from 43 to 89 depending onthe care practice assessed [3ndash5]Most attempts to improve adherence to standard precau-

tions up to this point have focused on educating HCPsabout the rationale and application of transmission-basedprecautions While such initiatives have resulted in im-proved knowledge and attitudes they usually lack an ac-companying sustained change in behaviour [6 7] It hasbeen suggested that HCP compliance with guidelines maybe suboptimal due to high levels of ambiguity surroundingtasks (eg not knowing which guidelines are applicable)and expectations (eg not knowing what practice is accept-able or feasible) [8] and high cognitive load of HCPs [9] Inresponse to the challenge of changing behaviour increas-ing attention is paid to the role of environmental restruc-turing approaches that incorporate human factors designelements to improve adherence [10] One such opportunityfor incorporation of human factors principles is the designof signage indicating which precautions should be usedand when at the place where their use is indicatedSignage in healthcare like in other settings is used for

communication with people with different languagesages and physiological challenges [11] In healthcarespecifically signage should also communicate effectivelywith different categories of HCPs who in the case of iso-lation precautions may require different informationand even with patients and their visitors [12] Such sign-age should act as cognitive aids in the form of visualcues [13] and should remove ambiguity surroundingwhich precautions are necessary when treating isolatedpatients Thus these and several human factors consid-erations should be taken into account when designingand implementing such signageParticipatory design a user-centred design method-

ology in which end-users are actively involved in the de-sign process creates the opportunity to benefit from theexperience and expertise of key stakeholders [14] Par-ticipatory design methodology is well suited for use inhealthcare as it establishes a collaboration with frontlineHCPs to develop practical solutions that correspondwith frontline needs [15] This project utilised humanfactors engineering principles and a user-centred partici-patory design approach to design a signage system that1) provides visual cues and 2) removes ambiguity forHCPs about which precautions should be taken whentreating isolated patients

MethodsStudy designThe human factors-informed user-centred participatorydesign process employed in this project was composedof four stages each resulting in an output that informedthe subsequent activities throughout the iterative designlifecycle shown in Fig 1 and described in the following

sections [16] The participatory process was facilitatedby a psychologist with training in human factors engin-eering and extensive experience in the field of infectionprevention and control (LC) An infection control nurse(MM) and two infectious diseases physicians (AW HS)provided expert input throughout the process Thesefour individuals composed the design team

Study setting and participantsThis project was carried out at the University Hospitalof Zurich (USZ) a 900-bed university-affiliated tertiarycare hospital in 2014ndash2016 It was initiated in responseto low reported adherence to isolation precautions andnumerous critical incident reports related to isolationprecautions The project aimed to introduce signage foruniversal use throughout the hospital Successful imple-mentation of the new signage would require its use byseveral professional categories of HCPs (eg nurses phy-sicians allied-care professionals assistants) and hospitalstaff (eg housekeeping) working in several hospital set-tings (eg intensive care emergency general wards) Par-ticipants for each phase of the design process were thuspurposefully sampled by professional category and bywork setting in order to include a representative sampleof potential users of the system (Fig 1)

Establishing design requirements ndash interviews andobservationsTwo primary methods were used to establish design re-quirements that would inform the subsequent signagedesign 1) interviews with front-end users and 2) directobservations We conducted semi-structured interviewswith anticipated typical users of the isolation signagesystem and explored how isolation precautions are gen-erally handled (Could you walk me through the process ofhow new isolated patients are handled) how isolationprecautions are communicated in their unit (How do youknow what isolation status a certain patient has whichprecautions to use) and any suggestions they had to im-prove the current system (How do you feel about thecurrent isolation precaution signs Would you have anyrecommendations to improve) Interviews were docu-mented with detailed notes Direct unstructured obser-vations were conducted in a representative sample ofhospital settings (intensive care emergency generalward) with the purpose of observing multiple types ofusers interacting with the existing signage Observationswere documented through field notes and photosFollowing initial observations and interviews personas

representing distinct user groups were established thatcollectively describe the potential user population [17]The design team established personas based on user pat-terns identified during interviews and observationsThese personas were used by the design team and

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 2 of 13

workshop participants to keep all potential users of thesignage in mind and make sure that design alternativeswere meeting the goals and needs of specific users Furthera list of established design requirements was established asan evolving document that was refined throughout the de-sign lifecycle with ongoing data collection Throughout thisprocess both functional and non-functional design require-ments were identified Functional requirements describedwhat the system should do in order to serve its purposewhereas non-functional requirements concerned the phys-ical social environmental and technical constraints placedon the system design and its development [16]

Designing alternatives ndash design thinking workshopsWe conducted design thinking workshops with frontlineHCPs based on an adapted methodology from the Stan-ford University Institute of Design including modes ofempathising defining ideating and prototyping [18]Participants grouped into pairs were first prompted tointerview their partners about the current challengessurrounding communication of isolation precautions(empathising) and then to synthesise information and in-sights from the interview into ldquoproblem statementsrdquo thatdescribed meaningful user challenges (defining) Based onthese problem statements participants then completed

several ideation activities to generate new ideas and solu-tions ndash exchanging ideas and sharing feedback with theirpartner after each step (ideating) As a final step partici-pants used provided materials to create a prototype oftheir solution for communicating isolation precautions(prototyping) Workshop activities were documented withphotos detailed notes and collected worksheets Work-shop documentation was then included in a qualitativeanalysis whereby all data was reviewed and grouped intothematic categories

Prototyping and evaluationBuilding on the established list of design requirementsdesign ideas and initial prototypes generated during theprevious design phases a process of iterative prototypingand user-testing began Low-fidelity prototypes wereproduced using paper and pencil sketches while higher-fidelity prototypes were produced using graphics soft-ware [19ndash21] This process consisted of multiple cyclesof user evaluation with continuous feedback from HCPsto make modifications to the prototype which was thenre-evaluatedDuring the prototyping phase symbols representing

each isolation category (contact droplet and isolation)were also developed to be included in the overall

Fig 1 User-centred design process Legend Multiple methods were employed for each phase of the user-centred design process Participantswere purposefully recruited for each study phase to include a broad range of potential users of the system ID infectious diseases IPC infectionprevention and control

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 3 of 13

isolation signage system Multiple variants of eachsymbol were evaluated through symbol judgement testsand comprehensibility tests using paper-based surveysaccording to the methodology proposed by ISO 9186[22] During symbol judgement tests participants weresuccessively shown several variants of a symbol and itsintended meaning Participants were asked to estimatethe percentage (from 0 to 100) of HCPs and visitors tothe hospital that could be expected to understand themeaning of each variant The order with which variantsof each symbol were presented was randomised for eachsurvey to avoid order bias The variants of each symbolwith highest average score during judgement testingmeaning those that participants judged as being mostlikely to be understood were then assessed throughcomprehensibility testing during which a new group ofparticipants were presented with a symbol and an imagedemonstrating the context in which they might find itParticipants were then asked to write exactly what theythink the symbol means and what actions they shouldtake in response to the symbol Each participant saw onevariant of each symbol and six different test versionswere created with the order and combination of symbolsrandomised The variant of each symbol with the highestpercentage of correct responses was deemed the mostcomprehensible and was retained for further use duringiterative prototyping and evaluation of the overall isola-tion signageThe final signage prototypes underwent observations

and expert review with infection prevention experts priorto being finalised by a professional graphic designer

ResultsEstablishing design requirements ndash results of interviewsand observationsThe existing isolation signage system in our hospital wascomposed of a single poster for HCPs indicating onlythat ldquospecial precautionsrdquo were necessary and that visi-tors should contact the nursersquos station (Fig 2) Add-itional signs existed for housekeeping personnel whichindicated the category of isolation which protectivemeasures were applicable and which disinfecting agentsshould be used (Fig 2)Observations and interviews revealed several barriers

to use of the existing isolation signage system Thesebarriers are presented in the following sections

Confusion about target audienceWhen asked where they located information regardingisolation precaution measures several HCPs erroneouslyreferred to signage intended for housekeeping personnelThis was likely due to the inconspicuous or missing indi-cation regarding for whom the signs were intended Fur-ther existing signage for HCPs simply indicated ldquoSTOPspecial infection prevention precautionsrdquo without indi-cating the type of isolation or which specific precautionsapply whereas signage for housekeeping personnel indi-cated specific precautions intended for cleaning proce-dures according to the isolation type HCPs searchingfor specific guidance were frequently observed mistakinghousekeeping measures eg wearing gloves to protectskin from abrasive detergents as intended for them

Fig 2 Existing isolation signage intended for healthcare providers for all isolation categories (left) and for housekeeping personnel specific tocontact isolation (right) Legend These signs have been translated from German to English for publication

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 4 of 13

SaliencyThe existing signage for HCPs was placed next to or dir-ectly on the door of patients in single rooms togetherwith an isolation cart with all necessary protective mate-rials (eg gloves gowns masks) The isolation signagewas often one of many posted signs and HCPs reportedthat the colours were not salient relative to other sign-age meaning that the signs frequently went unnoticedOn intensive care units with patient bays rather thansingle rooms signage was attached to isolation carts po-sitioned near to the patient space When the isolationsignage was attached to the isolation cart HCPs re-ported that it did not provide a salient visual cue be-cause of the low signal-to-noise ratio Interviewed HCPsshared that this resulted in them unknowingly enteringinto to spaces of isolated patients

Trade-off between simplicity and complexityThe existing signage for HCPs neither indicated the cat-egory of isolation nor the necessary precautions to betaken Observations of these signs in use revealed thatHCPs desired more point-of-care information and theyaccordingly developed ldquopatchesrdquo whereby they addedstickers or wrote directly on the existing signage to addmissing information such as the category of isolation(Fig 3) Alternatively a simplifying ldquopatchrdquo had alsobeen applied to the detailed housekeeping signsWhereas the original sign indicated that a surgical maskldquomay be necessaryrdquo and that this should be discussedwith nursing personnel the patch saying ldquowith maskrdquo re-moved ambiguity and explicitly indicated the need todon a mask when cleaning the rooms of patients withnorovirus (Fig 4)

Method ambiguityWhile some HCPs were able to cite the personal pro-tective equipment (ie mask gown) necessary for eachcategory of isolation many were unsure about the orderwith which these should be donned and doffed andwhen hand hygiene should be performed when enteringand exiting the patient room

PersonasFollowing interviews and observations five personaswere established to embody the identified goals andneeds of key users of the signage system and to guidethe rest of the design process (Table 1) These personaswere printed and referred to throughout the subsequentstudy phases to keep a user-centred focus and to remindthe design team and participating HCPs about the rangeof user needs to be considered

List of design requirementsThe information gathered during interviews and observa-tions were used to establish a list of functional and non-functional design requirements (Table 2) Additional designrequirements were subsequently added to this evolvingdocument throughout the design process The functionalrequirements primarily concerned information that thesignage should provide to different categories of personneland visitors are alerted and informed about the necessaryisolation precautions The non-functional requirementsconcerned the aspects of the signage that are required tomake it compatible with the overall environment to whichit will be introduced as well as non-functional requirementson the system level that needed to be addressed for thesignage system to function optimally One such require-ment is that the signage must be consistent with corporatedesign guidelines at the USZ which indicate the coloursand fonts that should be used for internal and externalcommunication

Designing alternatives ndash design thinking workshopsTwo ideation workshops were conducted Several recur-ring themes were identified as discussed in the followingsections

Forcing functionSeveral workshop participants presented ideas that em-ploy the engineering concept of forcing function abehaviour-shaping constraint in order to ensure compli-ance with isolation precautions During one workshopparticipants working on the problem statement ldquohowmight we ensure that required isolation measures arerespected 100 of the timerdquo ideated around forcingfunction solutions to detect if appropriate personalprotective equipment had been donned prior to openingthe patient door (Fig 5) Due to safety and feasibility

Fig 3 Existing signage for healthcare providers with ldquopatchrdquo toindicate category of isolation Legend This ldquopatchrdquo introduced byhealthcare providers demonstrates that the existing signage was notoffering sufficient information and that healthcare providers wantedthe signage to indicate the category of isolation The patchindicated with an arrow reads ldquocontact isolationrdquo

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 5 of 13

concerns with this idea during the prototyping phasethese participants instead employed masks suspended inthe doorway through which healthcare providers mustwalk thereby automatically donning a mask upon roomentry Such solutions must be assessed to ensure theirsafety prior to introduction Employing such forcingfunctions would address issues of forgetting which par-ticipants confirmed is one of the main reasons for pro-cedural noncompliance

Not ldquobreaking the flow of workrdquoSeveral participants expressed that a major barrier tocompliance with isolation precautions is the time neces-sary to find out which precautions are applicable and lo-cate and don the materials necessary for complianceThis was expressed in the problem statement ldquohowmight we save time while respecting isolation precau-tionsrdquo Participants proposed multiple solutions Indicat-ing on the signage both the type of isolation as well asthe necessary precautions eliminates the cognitive loadrequired for those entering the room and saves time ne-cessary to identify the relevant guidelines and materialsFigure 6 demonstrates both the ideation and prototypingof one such solution which sends a strong visual cue in-dicating the type of protective equipment that should beemployed

Placement of visual cuesAnother theme identified during the workshops was thatthe current provision of visual cues (only at the entranceto the patient room) is inadequate When prompted

about where visual cues should be located the majorityof participants indicated that some cues should also belocated inside the patient room The most commonlyproposed locations for visual cues included at the en-trance to the patient room at the foot of the patientbed and next to patient charts

Prototyping and evaluationSymbol development and judgement testDuring design thinking workshops participants gener-ated ideas and sketches about how to portray the threemain isolation categories (contact droplet and airborne)as symbols (Additional file 1) Variants of each isolationsymbol [contact isolation (n = 4) droplet isolation (n =5) and airborne isolation (n = 6)] were then designedemploying the same themes that emerged from the par-ticipants themselves in order to be consistent with usermental models and thus increase comprehension Re-spondentsrsquo judgements of how many of their colleagueswould understand the symbols ranged from 17 to 78(Additional file 2) Of note the variants that picturedtwo whole human figures performed better in judgementtesting than those without the human figure or part ofthe human body (eg only hands) The highest rated var-iants of each symbol were retained and further examinedthrough a comprehensibility test

Symbol comprehensibility testDetailed results of the comprehensibility testing can befound in Additional file 2 Whereas the symbols for con-tact and droplet isolation were correctly understood by a

Fig 4 Existing signage for housekeeping (left) with ldquopatchrdquo to clarify ambiguous mask indication (right) Legend This ldquopatchrdquo introduced byhousekeeping personnel suggests that the existing signage provided ambiguous instructions and that they preferred a more simple instructionto don a mask The patch indicated with an arrow reads ldquowith maskrdquo instead of ldquosurgical mask if necessaryrdquo The existing signage (left) wastranslated from German to English for publication

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 6 of 13

Table 1 Established personas

Persona Description User requirements

Julia Internal Medicine NurseAge 25

bull Julia began working in the internal medicine ward atthe USZ directly after finishing her nursing degreeHaving freshly finished her schooling she looks up tothe more experienced nurses

bull She is especially vigilant in her infection controlpractices including isolation precautions as this was amajor focus of her training

bull When she is not sure about which isolation precautionsshe should use for a patient she (erroneously)references the sign on the housekeeping cart

bull Signage should offer multiple levels of information forfrequent versus rare users For example recognition ofthe standardised signage colour may be enough forfrequent users to recall the necessary precautionswhereas rare users need to be reminded of the specificprecautions

bull Target audience must be clearly distinguishable

Sarah Nursing assistantAge 48

bull Sarah has worked in several wards of the USZ One ofthe highlights of her job is that it allows her to have aclose relationship with patients

bull She has a hard time bringing up isolation with herpatients because she sympathises with the emotionaleffects this may have For the same reason shesometimes neglects to respect hygiene measures suchas hand hygiene and wearing gowns as she feels thisputs a separation between herself and the patient

bull Signage should aim to establish social norms increaseacceptability of performing infection preventionmeasures

Paul Emergency WardPhysician Age 42

bull During medical school in Germany Paul chose tospecialise in emergency medicine because Dr Housewas his favourite TV drama and he enjoys the challengeand rush to resolve critical situations

bull Paulrsquos career took off quickly after he successfullypublished a highly cited paper in New England Journalof Medicine and he became known as an expert influid management in poly-trauma patients

bull In the rush of acute care situations infection controlmeasures sometimes take a back seat but no one daresto correct this senior physician

bull Signage must quickly communicate essentialinformation and must not require extra time

bull Barriers to performing isolation precautions (egmissing materials) should be removed

bull Signage should aim to support psychological safety(eg speaking up)

Omar Porter Age 55 bull Prior to moving to Switzerland with his family five yearsago Omar was an elementary school teacher in TunisiaHe came to Switzerland with no prior Germanknowledge but was able to begin working in thehospital while simultaneously taking German classes

bull When he began working he relied on clear photos andsymbols to help him interpret written protocols

bull Signage must be able to communicate effectively withstaff for whom German is not a native language forexample with self-explanatory images

Teresa Housekeeping staffAge 46

bull Teresa is specially assigned to work in the emergencyward where they have specific cleaning andmaintenance procedures from the rest of the hospitalHer native language is Portuguese but her outgoingpersonality helped her to quickly learn German throughchatting with her colleagues when she began working

bull Signage content may need to be adapted for specificsettings

bull Signage must be able to communicate effectively withstaff for whom German is not a native language forexample with self-explanatory images

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 7 of 13

majority of participants the symbols for airborne isola-tion were sometimes incorrectly interpreted as meaningdroplet isolation The three variants with the highestcomprehensibility and least conflicting interpretationswere retained for use in further signage prototypes(Fig 7)

Iterative prototyping and evaluationThe process of iterative prototyping and evaluation of iso-lation signage occurred in parallel to the testing of sym-bols During this process several prototypes emerged withvarying levels of sophistication In the earliest stages ideaswere expressed on paper in the form of sketches Thosesketches with the most positive feedback from the targetpopulation were then transformed into more sophisticatedprototypes As prototypes were continually evaluatedthrough informal discussions with frontline HCPs theirfeedback provided insights that led to further refining ofconsecutive prototypes Experts in infection preventionand control were regularly consulted to ensure accuracyof the signage content This iterative design process asdocumented in Additional file 3 continued until satur-ation was achieved (ie until no new feedback was given)

Final signage solutionThe final solutions that resulted from the iterative proto-typing and evaluation process were shared with agraphic designer to produce the final signage system forthe three main isolation categories (Fig 8) as well as twosigns for combined precautions (Fig 9) This solutionfeatures a caution tape graphic and salient colours todraw attention to those entering the room that specialprecautions must be taken The isolation categories arecommunicated dually through the colour which is stan-dardised throughout all isolation precaution documentsand the prominent symbol portraying the transmissionpathway The specific precautions are portrayed in theorder in which they must be performed removing

method ambiguity The use of text is limited and thesignage relies largely on user-friendly graphics to sup-port comprehension regardless of language proficiencyThe signage is available for download on the intranetand can be printed with one sign per A4 sheet of paperBeyond the scope of the physical signage hospital guide-lines have also been introduced that limit the amountand type of information that can be posted on patientdoors which increases the saliency of remaining signageIn collaboration with the infection prevention depart-ment the housekeeping department has also revisedtheir isolation precaution guidelines and brochures toeliminate confusion with signage intended for HCPsThe signs were implemented by e-mailing heads of

wards to inform them of the new signage announce-ment and posting of the new signs on the intranet ser-ver and physically distributing printed signs to eachhospital ward according to number of beds Additionalcopies were made available for order Physical copiesand links to the previous signage were removed

DiscussionThis paper describes the successful application of a user-centred participatory design process to develop a sign-age system for communicating isolation precautionsThe resulting signage system aims to serve as a visualcue for HCPs remove ambiguity and elicit safe infectionprevention behaviours to ultimately prevent the trans-mission of infectious agentsOur analysis of existing isolation signage revealed that

ambiguity was indeed a major factor responsible fornon-compliance with transmission-based precautions inour hospital This is consistent with the findings ofGurses et al who propose systems ambiguity as aframework to explain procedural non-compliance inhealthcare [8] Ambiguity in our institution was identi-fied mainly in the form of task ambiguity (not knowingwhich guidelines are applicable for which patients) and

Table 1 Established personas (Continued)

Persona Description User requirements

at the USZ even picking up a Swiss German accentbull She has been working in the emergency ward for 12years now and although she has no medical trainingshe is excellent at what she does

Legend Personas fictional characters based on input from real users were established to understand the needs and goals of the individuals who will interactwith the signage system and to guide the subsequent design process

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 8 of 13

method ambiguity (not knowing how or in which orderto complete a particular guideline) This was due to thelack of indication about which category of isolation a pa-tient was under or which preventative measures wereapplicable To specifically address barriers related to taskand method ambiguity the new signage was designedwith the intent of bringing isolation guidelines directlyto the frontline where their use is indicated also re-ferred to as placing ldquoknowledge in the worldrdquo [23 24]The symbols and colour-scheme developed to portray

isolation categories (contact droplet and airborne) weredeemed to be an important part of the overall signagewith the intention that these may become standardisedthroughout the institution and thus increase recognitionand compliance The comprehensibility evaluation ofthese symbols revealed that the airborne and droplet iso-lation symbols were the most often confounded This isnot surprising due to the similar means by which bothairborne particles and droplets can be propelled into theenvironment through coughing and sneezing In orderto further distinguish these symbols they have beenassociated in the new signage with standardised colourscheme where airborne is blue droplet is green andcontact is orange The standardisation of these colourschemes is intended to further aid in the distinction ofdifferent isolation categories and make them quicklyrecognisable once they have been learned through re-peated exposure

Table 2 Identified design requirements

Functional requirements (what the system should do)

Informationdissemination

bull Draw the attention of anyone entering the room thatspecial precautions must be taken

bull Inform any person entering the patient room whatisolation status that patient has

bull Inform any person entering the patient room aboutthe isolation precautions they must employ accordingto the patientrsquos isolation status

Inform healthcare personnel about requiredpersonal protective equipment

Inform cleaning staff about required protectiveequipment adapted disinfectants and prioritisedcleaning measures

Inform visitors about required personal protectiveequipment or instruct them to see a staff member

bull Inform any person entering the room about the orderin which precautions (eg donning and doffingpersonal protective equipment hand hygiene) shouldbe performed

bull Inform anyone transporting the patient about thetransmission-based precautions that shouldbe respected

bull In addition to the three main categories oftransmission-based precautions (contact droplet andairborne) signage should also be designed tocommunicate combined or ldquolightrdquo isolationprecautions specific to the USZ

USZ guidelines bull Be consistent with USZ guidelines for isolationprecautions The three main isolationcategories include

Contact isolation don gown Droplet isolation don surgical mask Airborne isolation don FFP2 mask

bull Communicate combined isolation precautions Contact + Droplet isolation don gown andsurgical mask

Contact + Airborne isolation don gown andFFP2 mask

Non-functional requirements(constraints on the system and its development)

Maintenancerestraints

bull Must be easy to hang and remove on an as-need basisbull If printed on paper must either be laminate so that itmay be cleaned and reused or single use

Accessibilityandconfidentialityrequirements

bull Should include graphics and symbols to accommodatenon-native German speaking personnel

bull Signage should avoid potential patient stigmatisationand should not disclose any confidentialpatient information

bull Signage must be accessible to individuals with colourvision deficiency for example by avoiding problematiccolour combinations and employing both colours andsymbols to convey messages over multiple channels

Physicalenvironmentrequirements

bull Signage must be noticeable relative to other signs inthe healthcare setting(appropriate single-to-noise ratio)

bull Some indication of the patientrsquos isolation statusshould travel with the patient at all times so that theappropriate transmission-based precautions can becommunicated at all times (eg when the patient isoutside of the room where the sign is posted) ndash thiscould be attached to the patient herself or to thepatientrsquos bed

bull Signage for housekeeping personnel should be of aportable size (A4 or smaller) so that it can fit on thecleaning trolleys

Organisational bull The signage should be able to quickly communicate

Table 2 Identified design requirements (Continued)

environmentrequirements

the required actions so that healthcare providers donot need to slow down (lsquobreak the rhythmrsquo) tointerpret them

bull If sign will be paper-based it should be easilyaccessible to staff on the ward when an isolatedpatient arrives (eg printed copies from intranet)or purchasable

bull Any posted signs must be consistent with theCorporate Design Guidelines

bull Information communicated through signage must beconsistent with evidence based-guidelines such as theCDC 2007 guidance as well as institutional infectioncontrol guidelines

Technicalenvironmentrequirements

bull Colour printer must be available if units are to printtheir own copies of paper-based signage

bull Intranet connection must be available if units are todownload the signs

bull Staff must be able to post the signage either by usingan adhesive material or the signs may be printeddirectly onto an adhesive sheet

bull Handling of signage material should be cost-effectiveand practical in every-day use

bull It should be possible to update the signage systemeasily in case new hospital rulesguidelinesare introduced

Legend Design requirements identified during interviews and observationsserved as a guide to ensure that subsequent designs met user needs whilesatisfying functional and non-functional requirements USZ University HospitalZurich CDC Centers for Disease Control

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 9 of 13

It is commonly accepted that ldquoconcept-relatedrdquo sym-bols which are abstract representations of the referentor subject they represent require more training beforethey can be understood by viewers [25] However by de-signing symbols for isolation precaution signage suchthat they are consistent with mental models this projectaimed to achieve a design that requires minimal trainingand that may also be intuitively understood Interest-ingly comprehensibility testing revealed that symbolsshowing the whole human figure were rated higher thanthose without the human figure or with an abstract partof the human body (eg only hands) This finding is con-sistent with results of the Hablamos Juntos Report who

evaluated the usability of several symbols for use in way-finding signage in hospital settings and found that symbolswith the whole human body were best understood [12]In addition to comprehensibility benefits including

the human figure particularly human eyes may be im-portant as it relates to emotional design Multiple studieshave examined the effect of images of human eyes oncooperative behaviour such as an ldquohonour systemrdquomethod of payment to an honesty box to pay for drinksin a coffee room [26] Such studies have found that thepresence of eye images act as a subtle cue and thatpeople paid as much as three times more often for theirdrinks when human eyes were displayed as opposed to

Fig 5 Workshop example of ldquoforcing functionrdquo during ideation (left) and prototyping (right) phases Legend This extract from a design thinkingworkshop shows one participantrsquos proposal to use a ldquoforcing functionrdquo to ensure that hands are disinfected prior to entry The middle shows adoor handle that only opens when alcohol is detected The right shows a prototype featuring the forcing function of a mask suspended in thedoorway through which clinicians must walk and thereby don masks upon room entry

Fig 6 Idea (left) and Prototype (right) of signage from design thinking workshop Legend This prototype developed during a design thinkingworkshop sends a strong visual cue about the necessary precautions The sign reads ldquoWarning before entering helliprdquo

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 10 of 13

when a neutral control image was displayed [27] Studiesin infection prevention settings however have hadmixed success in reproducing this effect [28ndash30] Furtherstudies on this topic are warranted to better understandhow signage may be employed to prime cooperative be-haviour and thus improve guideline adherenceThe field of infection prevention and patient safety is

rife with opportunities to actively include HCPs in user-centred design processes to improve healthcare environ-ments and practises The participatory design approachwas well suited for this inquiry as it allowed us to activelyinvolve stakeholders with essential insights thereby estab-lishing ownership and increasing chances of acceptanceand sustainability of the new signage The benefits of col-laborating with frontline HCPs extend beyond the scopeof the resulting design to also improve the image of theInfection Control department as a resource and to nurturethe possibility of further collaboration Recent reviews onthe use of participatory approaches such as experience-based co-design or co-production in which patients andhealthcare staff are engaged to improve health servicesreport outcomes related to the value of patient and staffinvolvement the quantity and quality of ideas and sugges-tions to modify practices and tangible changes in servicedelivery and user experience [31 32]Some limitations of this study should be considered

During this study we were faced with the challenge of

changing institutional guidelines for isolation precau-tions This prevented a quantitative analysis of change inpractice and presented a challenge during the evaluationwith frontline staff who were not yet familiar with thenew guidelines and thus had a tendency to focus on thediscrepancies between the ldquonewrdquo vs the current guide-lines rather than signage design The latter was ad-dressed through discussion with participants about thepossibility of new evidence-based practices and also bypresenting frontline users with prototypes that were con-sistent with their existing mental models ie consistentwith current guidelines Also the introduction of suchsignage is intended to serve as a visual cue and to re-move ambiguity regarding which precautions should beused and when The introduction of such signage how-ever does not entirely remove other known barriers tocompliance with isolation precautions such as ldquolack oftimerdquo [33] or ldquoavailability of protective clothingrdquo [5] It isthus imperative that the introduction of such signagetakes place within the context of a systems approach en-suring for example that the necessary time and materialresources are also available in order to mitigate thesebarriers

ConclusionsIn conclusion this study resulted in a user-centred sign-age design solution and set of comprehensible symbols

Fig 7 Symbols for contact (left) droplet (middle) and airborne (right) isolation Legend The variants of each symbol with the highest judgementand comprehensibility ratings were retained for use in further signage development phases

Fig 8 The final signage solution for contact (left) droplet (middle) and airborne (right) isolation Legend The final solution to be printed withone sign per A4 sheet incorporates several features to satisfy the identified design requirements These signs have been translated from Germanto English for publication

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 11 of 13

to remove ambiguity and to make compliance withevidence-based guidelines easy and intuitive for HCPsand visitors to the USZ The introduction of signageparticularly for infection control offers a promising op-portunity to make guidelines available directly at thefrontline where their use is indicated thereby reducingthe need for training and standard operating proceduresThis article further describes the application of a user-centred participatory design process which has great po-tential for application in the field of hospital infectioncontrol to design solutions that make performing infec-tion prevention behaviours easy and intuitive

Supplementary informationSupplementary information accompanies this paper at httpsdoiorg101186s13756-019-0629-9

Additional file 1 Pictorial portrayal of isolation categories

Additional file 2 Results of Judgement and Comprehension testing

Additional file 3 Iterations of Isolation Signage System

AbbreviationsCDC Centers for Disease Control HAI Healthcare-associated infectionsHCP Healthcare provider ID Infectious diseases IPC Infection preventionand control USZ University Hospital Zurich

AcknowledgementsWe would like to warmly acknowledge all study participants We would alsolike to acknowledge Andreacute Rothfuchs of Studio Sirup who provided graphicdesign services for the final signage solution

Authorsrsquo contributionsLC and HS conceived and designed the study LC conducted data collectionanalysis and iterative signage design and evaluation MS MM and AWprovided iterative feedback to inform the final signage solution LC draftedthe manuscript and all authors provided detailed feedback and approvedthe final manuscript

FundingThis work was partially funded by the Swiss National Science Foundation(32003B_149474) and by the University Hospital of Zurich Department ofQuality Management and Patient Safety

Availability of data and materialsThe datasets used andor analysed during the current study are availablefrom the corresponding author on reasonable request

Ethics approval and consent to participateThe Zurich Cantonal Ethics Committee waived the need for formal ethicsreview of this project (KEK-StV-Nr 4114) Participation in all study activitieswas voluntary and participants were free to withdraw at any time Allinterview and workshop participants provided written informed consentprior to participation

Consent for publicationNot applicable

Competing interestsThe authors declare that they have no competing interests

Author details1Division of Infectious Diseases and Hospital Epidemiology UniversityHospital Zurich and University of Zurich Raemistrasse 100 HAL14 8091Zurich Switzerland 2Department of Management Technology andEconomics ETH Zurich Zurich Switzerland

Received 9 August 2019 Accepted 16 October 2019

References1 World Health Organization (WHO) Report on the burden of endemic health

care-associated infection wordwide Geneva World Health Organization2011

2 Siegel JD Rhinehard E Jackson M et al 2007 guideline for isolationprecautions preventing transmission of infectious agents in healthcaresettings 2007

3 Larson E Kretzer EK Compliance with handwashing and barrier precautionsJ Hosp Infect 199530(Suppl)88ndash106

4 Weber D Sickbert-Bennett EE Brown VM et al Compliance withisolation precautions at a university hospital Infect Control HospEpidemiol 200728358ndash61

5 Gammon J Morgan-Samuel H Gould D A review of the evidence forsuboptimal compliance of healthcare practitioners to standarduniversalinfection control precautions J Clin Nurs 200817157ndash67 httpsdoiorg101111j1365-2702200601852x

6 Sax H Perneger T Hugonnet S et al Knowledge of standard and isolationprecautions in a large teaching hospital Infect Control Hosp Epidemiol200526298ndash304 httpsdoiorg101086502543

7 Sax H Uckay I Richet H et al Determinants of good adherence to handhygiene among healthcare workers who have extensive exposure to handhygiene campaigns Infect Control Hosp Epidemiol 2007281267ndash74httpsdoiorg101086521663

8 Gurses AP Seidl KL Vaidya V et al Systems ambiguity and guidelinecompliance a qualitative study of how intensive care units follow evidence-based guidelines to reduce healthcare-associated infections Qual Saf HealthCare 200817351ndash9 httpsdoiorg101136qshc2006021709

9 Grundgeiger T Sanderson PM Orihuela CB et al Prospective memoryin the ICU the effect of visual cues on task execution in arepresentative simulation Ergonomics 201356579ndash89 httpsdoiorg101080001401392013765604

Fig 9 The final signage solution for combined precautions Legend These signs have been translated from German to English for publication

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 12 of 13

workshop participants to keep all potential users of thesignage in mind and make sure that design alternativeswere meeting the goals and needs of specific users Furthera list of established design requirements was established asan evolving document that was refined throughout the de-sign lifecycle with ongoing data collection Throughout thisprocess both functional and non-functional design require-ments were identified Functional requirements describedwhat the system should do in order to serve its purposewhereas non-functional requirements concerned the phys-ical social environmental and technical constraints placedon the system design and its development [16]

Designing alternatives ndash design thinking workshopsWe conducted design thinking workshops with frontlineHCPs based on an adapted methodology from the Stan-ford University Institute of Design including modes ofempathising defining ideating and prototyping [18]Participants grouped into pairs were first prompted tointerview their partners about the current challengessurrounding communication of isolation precautions(empathising) and then to synthesise information and in-sights from the interview into ldquoproblem statementsrdquo thatdescribed meaningful user challenges (defining) Based onthese problem statements participants then completed

several ideation activities to generate new ideas and solu-tions ndash exchanging ideas and sharing feedback with theirpartner after each step (ideating) As a final step partici-pants used provided materials to create a prototype oftheir solution for communicating isolation precautions(prototyping) Workshop activities were documented withphotos detailed notes and collected worksheets Work-shop documentation was then included in a qualitativeanalysis whereby all data was reviewed and grouped intothematic categories

Prototyping and evaluationBuilding on the established list of design requirementsdesign ideas and initial prototypes generated during theprevious design phases a process of iterative prototypingand user-testing began Low-fidelity prototypes wereproduced using paper and pencil sketches while higher-fidelity prototypes were produced using graphics soft-ware [19ndash21] This process consisted of multiple cyclesof user evaluation with continuous feedback from HCPsto make modifications to the prototype which was thenre-evaluatedDuring the prototyping phase symbols representing

each isolation category (contact droplet and isolation)were also developed to be included in the overall

Fig 1 User-centred design process Legend Multiple methods were employed for each phase of the user-centred design process Participantswere purposefully recruited for each study phase to include a broad range of potential users of the system ID infectious diseases IPC infectionprevention and control

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 3 of 13

isolation signage system Multiple variants of eachsymbol were evaluated through symbol judgement testsand comprehensibility tests using paper-based surveysaccording to the methodology proposed by ISO 9186[22] During symbol judgement tests participants weresuccessively shown several variants of a symbol and itsintended meaning Participants were asked to estimatethe percentage (from 0 to 100) of HCPs and visitors tothe hospital that could be expected to understand themeaning of each variant The order with which variantsof each symbol were presented was randomised for eachsurvey to avoid order bias The variants of each symbolwith highest average score during judgement testingmeaning those that participants judged as being mostlikely to be understood were then assessed throughcomprehensibility testing during which a new group ofparticipants were presented with a symbol and an imagedemonstrating the context in which they might find itParticipants were then asked to write exactly what theythink the symbol means and what actions they shouldtake in response to the symbol Each participant saw onevariant of each symbol and six different test versionswere created with the order and combination of symbolsrandomised The variant of each symbol with the highestpercentage of correct responses was deemed the mostcomprehensible and was retained for further use duringiterative prototyping and evaluation of the overall isola-tion signageThe final signage prototypes underwent observations

and expert review with infection prevention experts priorto being finalised by a professional graphic designer

ResultsEstablishing design requirements ndash results of interviewsand observationsThe existing isolation signage system in our hospital wascomposed of a single poster for HCPs indicating onlythat ldquospecial precautionsrdquo were necessary and that visi-tors should contact the nursersquos station (Fig 2) Add-itional signs existed for housekeeping personnel whichindicated the category of isolation which protectivemeasures were applicable and which disinfecting agentsshould be used (Fig 2)Observations and interviews revealed several barriers

to use of the existing isolation signage system Thesebarriers are presented in the following sections

Confusion about target audienceWhen asked where they located information regardingisolation precaution measures several HCPs erroneouslyreferred to signage intended for housekeeping personnelThis was likely due to the inconspicuous or missing indi-cation regarding for whom the signs were intended Fur-ther existing signage for HCPs simply indicated ldquoSTOPspecial infection prevention precautionsrdquo without indi-cating the type of isolation or which specific precautionsapply whereas signage for housekeeping personnel indi-cated specific precautions intended for cleaning proce-dures according to the isolation type HCPs searchingfor specific guidance were frequently observed mistakinghousekeeping measures eg wearing gloves to protectskin from abrasive detergents as intended for them

Fig 2 Existing isolation signage intended for healthcare providers for all isolation categories (left) and for housekeeping personnel specific tocontact isolation (right) Legend These signs have been translated from German to English for publication

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 4 of 13

SaliencyThe existing signage for HCPs was placed next to or dir-ectly on the door of patients in single rooms togetherwith an isolation cart with all necessary protective mate-rials (eg gloves gowns masks) The isolation signagewas often one of many posted signs and HCPs reportedthat the colours were not salient relative to other sign-age meaning that the signs frequently went unnoticedOn intensive care units with patient bays rather thansingle rooms signage was attached to isolation carts po-sitioned near to the patient space When the isolationsignage was attached to the isolation cart HCPs re-ported that it did not provide a salient visual cue be-cause of the low signal-to-noise ratio Interviewed HCPsshared that this resulted in them unknowingly enteringinto to spaces of isolated patients

Trade-off between simplicity and complexityThe existing signage for HCPs neither indicated the cat-egory of isolation nor the necessary precautions to betaken Observations of these signs in use revealed thatHCPs desired more point-of-care information and theyaccordingly developed ldquopatchesrdquo whereby they addedstickers or wrote directly on the existing signage to addmissing information such as the category of isolation(Fig 3) Alternatively a simplifying ldquopatchrdquo had alsobeen applied to the detailed housekeeping signsWhereas the original sign indicated that a surgical maskldquomay be necessaryrdquo and that this should be discussedwith nursing personnel the patch saying ldquowith maskrdquo re-moved ambiguity and explicitly indicated the need todon a mask when cleaning the rooms of patients withnorovirus (Fig 4)

Method ambiguityWhile some HCPs were able to cite the personal pro-tective equipment (ie mask gown) necessary for eachcategory of isolation many were unsure about the orderwith which these should be donned and doffed andwhen hand hygiene should be performed when enteringand exiting the patient room

PersonasFollowing interviews and observations five personaswere established to embody the identified goals andneeds of key users of the signage system and to guidethe rest of the design process (Table 1) These personaswere printed and referred to throughout the subsequentstudy phases to keep a user-centred focus and to remindthe design team and participating HCPs about the rangeof user needs to be considered

List of design requirementsThe information gathered during interviews and observa-tions were used to establish a list of functional and non-functional design requirements (Table 2) Additional designrequirements were subsequently added to this evolvingdocument throughout the design process The functionalrequirements primarily concerned information that thesignage should provide to different categories of personneland visitors are alerted and informed about the necessaryisolation precautions The non-functional requirementsconcerned the aspects of the signage that are required tomake it compatible with the overall environment to whichit will be introduced as well as non-functional requirementson the system level that needed to be addressed for thesignage system to function optimally One such require-ment is that the signage must be consistent with corporatedesign guidelines at the USZ which indicate the coloursand fonts that should be used for internal and externalcommunication

Designing alternatives ndash design thinking workshopsTwo ideation workshops were conducted Several recur-ring themes were identified as discussed in the followingsections

Forcing functionSeveral workshop participants presented ideas that em-ploy the engineering concept of forcing function abehaviour-shaping constraint in order to ensure compli-ance with isolation precautions During one workshopparticipants working on the problem statement ldquohowmight we ensure that required isolation measures arerespected 100 of the timerdquo ideated around forcingfunction solutions to detect if appropriate personalprotective equipment had been donned prior to openingthe patient door (Fig 5) Due to safety and feasibility

Fig 3 Existing signage for healthcare providers with ldquopatchrdquo toindicate category of isolation Legend This ldquopatchrdquo introduced byhealthcare providers demonstrates that the existing signage was notoffering sufficient information and that healthcare providers wantedthe signage to indicate the category of isolation The patchindicated with an arrow reads ldquocontact isolationrdquo

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 5 of 13

concerns with this idea during the prototyping phasethese participants instead employed masks suspended inthe doorway through which healthcare providers mustwalk thereby automatically donning a mask upon roomentry Such solutions must be assessed to ensure theirsafety prior to introduction Employing such forcingfunctions would address issues of forgetting which par-ticipants confirmed is one of the main reasons for pro-cedural noncompliance

Not ldquobreaking the flow of workrdquoSeveral participants expressed that a major barrier tocompliance with isolation precautions is the time neces-sary to find out which precautions are applicable and lo-cate and don the materials necessary for complianceThis was expressed in the problem statement ldquohowmight we save time while respecting isolation precau-tionsrdquo Participants proposed multiple solutions Indicat-ing on the signage both the type of isolation as well asthe necessary precautions eliminates the cognitive loadrequired for those entering the room and saves time ne-cessary to identify the relevant guidelines and materialsFigure 6 demonstrates both the ideation and prototypingof one such solution which sends a strong visual cue in-dicating the type of protective equipment that should beemployed

Placement of visual cuesAnother theme identified during the workshops was thatthe current provision of visual cues (only at the entranceto the patient room) is inadequate When prompted

about where visual cues should be located the majorityof participants indicated that some cues should also belocated inside the patient room The most commonlyproposed locations for visual cues included at the en-trance to the patient room at the foot of the patientbed and next to patient charts

Prototyping and evaluationSymbol development and judgement testDuring design thinking workshops participants gener-ated ideas and sketches about how to portray the threemain isolation categories (contact droplet and airborne)as symbols (Additional file 1) Variants of each isolationsymbol [contact isolation (n = 4) droplet isolation (n =5) and airborne isolation (n = 6)] were then designedemploying the same themes that emerged from the par-ticipants themselves in order to be consistent with usermental models and thus increase comprehension Re-spondentsrsquo judgements of how many of their colleagueswould understand the symbols ranged from 17 to 78(Additional file 2) Of note the variants that picturedtwo whole human figures performed better in judgementtesting than those without the human figure or part ofthe human body (eg only hands) The highest rated var-iants of each symbol were retained and further examinedthrough a comprehensibility test

Symbol comprehensibility testDetailed results of the comprehensibility testing can befound in Additional file 2 Whereas the symbols for con-tact and droplet isolation were correctly understood by a

Fig 4 Existing signage for housekeeping (left) with ldquopatchrdquo to clarify ambiguous mask indication (right) Legend This ldquopatchrdquo introduced byhousekeeping personnel suggests that the existing signage provided ambiguous instructions and that they preferred a more simple instructionto don a mask The patch indicated with an arrow reads ldquowith maskrdquo instead of ldquosurgical mask if necessaryrdquo The existing signage (left) wastranslated from German to English for publication

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 6 of 13

Table 1 Established personas

Persona Description User requirements

Julia Internal Medicine NurseAge 25

bull Julia began working in the internal medicine ward atthe USZ directly after finishing her nursing degreeHaving freshly finished her schooling she looks up tothe more experienced nurses

bull She is especially vigilant in her infection controlpractices including isolation precautions as this was amajor focus of her training

bull When she is not sure about which isolation precautionsshe should use for a patient she (erroneously)references the sign on the housekeeping cart

bull Signage should offer multiple levels of information forfrequent versus rare users For example recognition ofthe standardised signage colour may be enough forfrequent users to recall the necessary precautionswhereas rare users need to be reminded of the specificprecautions

bull Target audience must be clearly distinguishable

Sarah Nursing assistantAge 48

bull Sarah has worked in several wards of the USZ One ofthe highlights of her job is that it allows her to have aclose relationship with patients

bull She has a hard time bringing up isolation with herpatients because she sympathises with the emotionaleffects this may have For the same reason shesometimes neglects to respect hygiene measures suchas hand hygiene and wearing gowns as she feels thisputs a separation between herself and the patient

bull Signage should aim to establish social norms increaseacceptability of performing infection preventionmeasures

Paul Emergency WardPhysician Age 42

bull During medical school in Germany Paul chose tospecialise in emergency medicine because Dr Housewas his favourite TV drama and he enjoys the challengeand rush to resolve critical situations

bull Paulrsquos career took off quickly after he successfullypublished a highly cited paper in New England Journalof Medicine and he became known as an expert influid management in poly-trauma patients

bull In the rush of acute care situations infection controlmeasures sometimes take a back seat but no one daresto correct this senior physician

bull Signage must quickly communicate essentialinformation and must not require extra time

bull Barriers to performing isolation precautions (egmissing materials) should be removed

bull Signage should aim to support psychological safety(eg speaking up)

Omar Porter Age 55 bull Prior to moving to Switzerland with his family five yearsago Omar was an elementary school teacher in TunisiaHe came to Switzerland with no prior Germanknowledge but was able to begin working in thehospital while simultaneously taking German classes

bull When he began working he relied on clear photos andsymbols to help him interpret written protocols

bull Signage must be able to communicate effectively withstaff for whom German is not a native language forexample with self-explanatory images

Teresa Housekeeping staffAge 46

bull Teresa is specially assigned to work in the emergencyward where they have specific cleaning andmaintenance procedures from the rest of the hospitalHer native language is Portuguese but her outgoingpersonality helped her to quickly learn German throughchatting with her colleagues when she began working

bull Signage content may need to be adapted for specificsettings

bull Signage must be able to communicate effectively withstaff for whom German is not a native language forexample with self-explanatory images

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 7 of 13

majority of participants the symbols for airborne isola-tion were sometimes incorrectly interpreted as meaningdroplet isolation The three variants with the highestcomprehensibility and least conflicting interpretationswere retained for use in further signage prototypes(Fig 7)

Iterative prototyping and evaluationThe process of iterative prototyping and evaluation of iso-lation signage occurred in parallel to the testing of sym-bols During this process several prototypes emerged withvarying levels of sophistication In the earliest stages ideaswere expressed on paper in the form of sketches Thosesketches with the most positive feedback from the targetpopulation were then transformed into more sophisticatedprototypes As prototypes were continually evaluatedthrough informal discussions with frontline HCPs theirfeedback provided insights that led to further refining ofconsecutive prototypes Experts in infection preventionand control were regularly consulted to ensure accuracyof the signage content This iterative design process asdocumented in Additional file 3 continued until satur-ation was achieved (ie until no new feedback was given)

Final signage solutionThe final solutions that resulted from the iterative proto-typing and evaluation process were shared with agraphic designer to produce the final signage system forthe three main isolation categories (Fig 8) as well as twosigns for combined precautions (Fig 9) This solutionfeatures a caution tape graphic and salient colours todraw attention to those entering the room that specialprecautions must be taken The isolation categories arecommunicated dually through the colour which is stan-dardised throughout all isolation precaution documentsand the prominent symbol portraying the transmissionpathway The specific precautions are portrayed in theorder in which they must be performed removing

method ambiguity The use of text is limited and thesignage relies largely on user-friendly graphics to sup-port comprehension regardless of language proficiencyThe signage is available for download on the intranetand can be printed with one sign per A4 sheet of paperBeyond the scope of the physical signage hospital guide-lines have also been introduced that limit the amountand type of information that can be posted on patientdoors which increases the saliency of remaining signageIn collaboration with the infection prevention depart-ment the housekeeping department has also revisedtheir isolation precaution guidelines and brochures toeliminate confusion with signage intended for HCPsThe signs were implemented by e-mailing heads of

wards to inform them of the new signage announce-ment and posting of the new signs on the intranet ser-ver and physically distributing printed signs to eachhospital ward according to number of beds Additionalcopies were made available for order Physical copiesand links to the previous signage were removed

DiscussionThis paper describes the successful application of a user-centred participatory design process to develop a sign-age system for communicating isolation precautionsThe resulting signage system aims to serve as a visualcue for HCPs remove ambiguity and elicit safe infectionprevention behaviours to ultimately prevent the trans-mission of infectious agentsOur analysis of existing isolation signage revealed that

ambiguity was indeed a major factor responsible fornon-compliance with transmission-based precautions inour hospital This is consistent with the findings ofGurses et al who propose systems ambiguity as aframework to explain procedural non-compliance inhealthcare [8] Ambiguity in our institution was identi-fied mainly in the form of task ambiguity (not knowingwhich guidelines are applicable for which patients) and

Table 1 Established personas (Continued)

Persona Description User requirements

at the USZ even picking up a Swiss German accentbull She has been working in the emergency ward for 12years now and although she has no medical trainingshe is excellent at what she does

Legend Personas fictional characters based on input from real users were established to understand the needs and goals of the individuals who will interactwith the signage system and to guide the subsequent design process

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 8 of 13

method ambiguity (not knowing how or in which orderto complete a particular guideline) This was due to thelack of indication about which category of isolation a pa-tient was under or which preventative measures wereapplicable To specifically address barriers related to taskand method ambiguity the new signage was designedwith the intent of bringing isolation guidelines directlyto the frontline where their use is indicated also re-ferred to as placing ldquoknowledge in the worldrdquo [23 24]The symbols and colour-scheme developed to portray

isolation categories (contact droplet and airborne) weredeemed to be an important part of the overall signagewith the intention that these may become standardisedthroughout the institution and thus increase recognitionand compliance The comprehensibility evaluation ofthese symbols revealed that the airborne and droplet iso-lation symbols were the most often confounded This isnot surprising due to the similar means by which bothairborne particles and droplets can be propelled into theenvironment through coughing and sneezing In orderto further distinguish these symbols they have beenassociated in the new signage with standardised colourscheme where airborne is blue droplet is green andcontact is orange The standardisation of these colourschemes is intended to further aid in the distinction ofdifferent isolation categories and make them quicklyrecognisable once they have been learned through re-peated exposure

Table 2 Identified design requirements

Functional requirements (what the system should do)

Informationdissemination

bull Draw the attention of anyone entering the room thatspecial precautions must be taken

bull Inform any person entering the patient room whatisolation status that patient has

bull Inform any person entering the patient room aboutthe isolation precautions they must employ accordingto the patientrsquos isolation status

Inform healthcare personnel about requiredpersonal protective equipment

Inform cleaning staff about required protectiveequipment adapted disinfectants and prioritisedcleaning measures

Inform visitors about required personal protectiveequipment or instruct them to see a staff member

bull Inform any person entering the room about the orderin which precautions (eg donning and doffingpersonal protective equipment hand hygiene) shouldbe performed

bull Inform anyone transporting the patient about thetransmission-based precautions that shouldbe respected

bull In addition to the three main categories oftransmission-based precautions (contact droplet andairborne) signage should also be designed tocommunicate combined or ldquolightrdquo isolationprecautions specific to the USZ

USZ guidelines bull Be consistent with USZ guidelines for isolationprecautions The three main isolationcategories include

Contact isolation don gown Droplet isolation don surgical mask Airborne isolation don FFP2 mask

bull Communicate combined isolation precautions Contact + Droplet isolation don gown andsurgical mask

Contact + Airborne isolation don gown andFFP2 mask

Non-functional requirements(constraints on the system and its development)

Maintenancerestraints

bull Must be easy to hang and remove on an as-need basisbull If printed on paper must either be laminate so that itmay be cleaned and reused or single use

Accessibilityandconfidentialityrequirements

bull Should include graphics and symbols to accommodatenon-native German speaking personnel

bull Signage should avoid potential patient stigmatisationand should not disclose any confidentialpatient information

bull Signage must be accessible to individuals with colourvision deficiency for example by avoiding problematiccolour combinations and employing both colours andsymbols to convey messages over multiple channels

Physicalenvironmentrequirements

bull Signage must be noticeable relative to other signs inthe healthcare setting(appropriate single-to-noise ratio)

bull Some indication of the patientrsquos isolation statusshould travel with the patient at all times so that theappropriate transmission-based precautions can becommunicated at all times (eg when the patient isoutside of the room where the sign is posted) ndash thiscould be attached to the patient herself or to thepatientrsquos bed

bull Signage for housekeeping personnel should be of aportable size (A4 or smaller) so that it can fit on thecleaning trolleys

Organisational bull The signage should be able to quickly communicate

Table 2 Identified design requirements (Continued)

environmentrequirements

the required actions so that healthcare providers donot need to slow down (lsquobreak the rhythmrsquo) tointerpret them

bull If sign will be paper-based it should be easilyaccessible to staff on the ward when an isolatedpatient arrives (eg printed copies from intranet)or purchasable

bull Any posted signs must be consistent with theCorporate Design Guidelines

bull Information communicated through signage must beconsistent with evidence based-guidelines such as theCDC 2007 guidance as well as institutional infectioncontrol guidelines

Technicalenvironmentrequirements

bull Colour printer must be available if units are to printtheir own copies of paper-based signage

bull Intranet connection must be available if units are todownload the signs

bull Staff must be able to post the signage either by usingan adhesive material or the signs may be printeddirectly onto an adhesive sheet

bull Handling of signage material should be cost-effectiveand practical in every-day use

bull It should be possible to update the signage systemeasily in case new hospital rulesguidelinesare introduced

Legend Design requirements identified during interviews and observationsserved as a guide to ensure that subsequent designs met user needs whilesatisfying functional and non-functional requirements USZ University HospitalZurich CDC Centers for Disease Control

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 9 of 13

It is commonly accepted that ldquoconcept-relatedrdquo sym-bols which are abstract representations of the referentor subject they represent require more training beforethey can be understood by viewers [25] However by de-signing symbols for isolation precaution signage suchthat they are consistent with mental models this projectaimed to achieve a design that requires minimal trainingand that may also be intuitively understood Interest-ingly comprehensibility testing revealed that symbolsshowing the whole human figure were rated higher thanthose without the human figure or with an abstract partof the human body (eg only hands) This finding is con-sistent with results of the Hablamos Juntos Report who

evaluated the usability of several symbols for use in way-finding signage in hospital settings and found that symbolswith the whole human body were best understood [12]In addition to comprehensibility benefits including

the human figure particularly human eyes may be im-portant as it relates to emotional design Multiple studieshave examined the effect of images of human eyes oncooperative behaviour such as an ldquohonour systemrdquomethod of payment to an honesty box to pay for drinksin a coffee room [26] Such studies have found that thepresence of eye images act as a subtle cue and thatpeople paid as much as three times more often for theirdrinks when human eyes were displayed as opposed to

Fig 5 Workshop example of ldquoforcing functionrdquo during ideation (left) and prototyping (right) phases Legend This extract from a design thinkingworkshop shows one participantrsquos proposal to use a ldquoforcing functionrdquo to ensure that hands are disinfected prior to entry The middle shows adoor handle that only opens when alcohol is detected The right shows a prototype featuring the forcing function of a mask suspended in thedoorway through which clinicians must walk and thereby don masks upon room entry

Fig 6 Idea (left) and Prototype (right) of signage from design thinking workshop Legend This prototype developed during a design thinkingworkshop sends a strong visual cue about the necessary precautions The sign reads ldquoWarning before entering helliprdquo

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 10 of 13

when a neutral control image was displayed [27] Studiesin infection prevention settings however have hadmixed success in reproducing this effect [28ndash30] Furtherstudies on this topic are warranted to better understandhow signage may be employed to prime cooperative be-haviour and thus improve guideline adherenceThe field of infection prevention and patient safety is

rife with opportunities to actively include HCPs in user-centred design processes to improve healthcare environ-ments and practises The participatory design approachwas well suited for this inquiry as it allowed us to activelyinvolve stakeholders with essential insights thereby estab-lishing ownership and increasing chances of acceptanceand sustainability of the new signage The benefits of col-laborating with frontline HCPs extend beyond the scopeof the resulting design to also improve the image of theInfection Control department as a resource and to nurturethe possibility of further collaboration Recent reviews onthe use of participatory approaches such as experience-based co-design or co-production in which patients andhealthcare staff are engaged to improve health servicesreport outcomes related to the value of patient and staffinvolvement the quantity and quality of ideas and sugges-tions to modify practices and tangible changes in servicedelivery and user experience [31 32]Some limitations of this study should be considered

During this study we were faced with the challenge of

changing institutional guidelines for isolation precau-tions This prevented a quantitative analysis of change inpractice and presented a challenge during the evaluationwith frontline staff who were not yet familiar with thenew guidelines and thus had a tendency to focus on thediscrepancies between the ldquonewrdquo vs the current guide-lines rather than signage design The latter was ad-dressed through discussion with participants about thepossibility of new evidence-based practices and also bypresenting frontline users with prototypes that were con-sistent with their existing mental models ie consistentwith current guidelines Also the introduction of suchsignage is intended to serve as a visual cue and to re-move ambiguity regarding which precautions should beused and when The introduction of such signage how-ever does not entirely remove other known barriers tocompliance with isolation precautions such as ldquolack oftimerdquo [33] or ldquoavailability of protective clothingrdquo [5] It isthus imperative that the introduction of such signagetakes place within the context of a systems approach en-suring for example that the necessary time and materialresources are also available in order to mitigate thesebarriers

ConclusionsIn conclusion this study resulted in a user-centred sign-age design solution and set of comprehensible symbols

Fig 7 Symbols for contact (left) droplet (middle) and airborne (right) isolation Legend The variants of each symbol with the highest judgementand comprehensibility ratings were retained for use in further signage development phases

Fig 8 The final signage solution for contact (left) droplet (middle) and airborne (right) isolation Legend The final solution to be printed withone sign per A4 sheet incorporates several features to satisfy the identified design requirements These signs have been translated from Germanto English for publication

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 11 of 13

to remove ambiguity and to make compliance withevidence-based guidelines easy and intuitive for HCPsand visitors to the USZ The introduction of signageparticularly for infection control offers a promising op-portunity to make guidelines available directly at thefrontline where their use is indicated thereby reducingthe need for training and standard operating proceduresThis article further describes the application of a user-centred participatory design process which has great po-tential for application in the field of hospital infectioncontrol to design solutions that make performing infec-tion prevention behaviours easy and intuitive

Supplementary informationSupplementary information accompanies this paper at httpsdoiorg101186s13756-019-0629-9

Additional file 1 Pictorial portrayal of isolation categories

Additional file 2 Results of Judgement and Comprehension testing

Additional file 3 Iterations of Isolation Signage System

AbbreviationsCDC Centers for Disease Control HAI Healthcare-associated infectionsHCP Healthcare provider ID Infectious diseases IPC Infection preventionand control USZ University Hospital Zurich

AcknowledgementsWe would like to warmly acknowledge all study participants We would alsolike to acknowledge Andreacute Rothfuchs of Studio Sirup who provided graphicdesign services for the final signage solution

Authorsrsquo contributionsLC and HS conceived and designed the study LC conducted data collectionanalysis and iterative signage design and evaluation MS MM and AWprovided iterative feedback to inform the final signage solution LC draftedthe manuscript and all authors provided detailed feedback and approvedthe final manuscript

FundingThis work was partially funded by the Swiss National Science Foundation(32003B_149474) and by the University Hospital of Zurich Department ofQuality Management and Patient Safety

Availability of data and materialsThe datasets used andor analysed during the current study are availablefrom the corresponding author on reasonable request

Ethics approval and consent to participateThe Zurich Cantonal Ethics Committee waived the need for formal ethicsreview of this project (KEK-StV-Nr 4114) Participation in all study activitieswas voluntary and participants were free to withdraw at any time Allinterview and workshop participants provided written informed consentprior to participation

Consent for publicationNot applicable

Competing interestsThe authors declare that they have no competing interests

Author details1Division of Infectious Diseases and Hospital Epidemiology UniversityHospital Zurich and University of Zurich Raemistrasse 100 HAL14 8091Zurich Switzerland 2Department of Management Technology andEconomics ETH Zurich Zurich Switzerland

Received 9 August 2019 Accepted 16 October 2019

References1 World Health Organization (WHO) Report on the burden of endemic health

care-associated infection wordwide Geneva World Health Organization2011

2 Siegel JD Rhinehard E Jackson M et al 2007 guideline for isolationprecautions preventing transmission of infectious agents in healthcaresettings 2007

3 Larson E Kretzer EK Compliance with handwashing and barrier precautionsJ Hosp Infect 199530(Suppl)88ndash106

4 Weber D Sickbert-Bennett EE Brown VM et al Compliance withisolation precautions at a university hospital Infect Control HospEpidemiol 200728358ndash61

5 Gammon J Morgan-Samuel H Gould D A review of the evidence forsuboptimal compliance of healthcare practitioners to standarduniversalinfection control precautions J Clin Nurs 200817157ndash67 httpsdoiorg101111j1365-2702200601852x

6 Sax H Perneger T Hugonnet S et al Knowledge of standard and isolationprecautions in a large teaching hospital Infect Control Hosp Epidemiol200526298ndash304 httpsdoiorg101086502543

7 Sax H Uckay I Richet H et al Determinants of good adherence to handhygiene among healthcare workers who have extensive exposure to handhygiene campaigns Infect Control Hosp Epidemiol 2007281267ndash74httpsdoiorg101086521663

8 Gurses AP Seidl KL Vaidya V et al Systems ambiguity and guidelinecompliance a qualitative study of how intensive care units follow evidence-based guidelines to reduce healthcare-associated infections Qual Saf HealthCare 200817351ndash9 httpsdoiorg101136qshc2006021709

9 Grundgeiger T Sanderson PM Orihuela CB et al Prospective memoryin the ICU the effect of visual cues on task execution in arepresentative simulation Ergonomics 201356579ndash89 httpsdoiorg101080001401392013765604

Fig 9 The final signage solution for combined precautions Legend These signs have been translated from German to English for publication

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 12 of 13

isolation signage system Multiple variants of eachsymbol were evaluated through symbol judgement testsand comprehensibility tests using paper-based surveysaccording to the methodology proposed by ISO 9186[22] During symbol judgement tests participants weresuccessively shown several variants of a symbol and itsintended meaning Participants were asked to estimatethe percentage (from 0 to 100) of HCPs and visitors tothe hospital that could be expected to understand themeaning of each variant The order with which variantsof each symbol were presented was randomised for eachsurvey to avoid order bias The variants of each symbolwith highest average score during judgement testingmeaning those that participants judged as being mostlikely to be understood were then assessed throughcomprehensibility testing during which a new group ofparticipants were presented with a symbol and an imagedemonstrating the context in which they might find itParticipants were then asked to write exactly what theythink the symbol means and what actions they shouldtake in response to the symbol Each participant saw onevariant of each symbol and six different test versionswere created with the order and combination of symbolsrandomised The variant of each symbol with the highestpercentage of correct responses was deemed the mostcomprehensible and was retained for further use duringiterative prototyping and evaluation of the overall isola-tion signageThe final signage prototypes underwent observations

and expert review with infection prevention experts priorto being finalised by a professional graphic designer

ResultsEstablishing design requirements ndash results of interviewsand observationsThe existing isolation signage system in our hospital wascomposed of a single poster for HCPs indicating onlythat ldquospecial precautionsrdquo were necessary and that visi-tors should contact the nursersquos station (Fig 2) Add-itional signs existed for housekeeping personnel whichindicated the category of isolation which protectivemeasures were applicable and which disinfecting agentsshould be used (Fig 2)Observations and interviews revealed several barriers

to use of the existing isolation signage system Thesebarriers are presented in the following sections

Confusion about target audienceWhen asked where they located information regardingisolation precaution measures several HCPs erroneouslyreferred to signage intended for housekeeping personnelThis was likely due to the inconspicuous or missing indi-cation regarding for whom the signs were intended Fur-ther existing signage for HCPs simply indicated ldquoSTOPspecial infection prevention precautionsrdquo without indi-cating the type of isolation or which specific precautionsapply whereas signage for housekeeping personnel indi-cated specific precautions intended for cleaning proce-dures according to the isolation type HCPs searchingfor specific guidance were frequently observed mistakinghousekeeping measures eg wearing gloves to protectskin from abrasive detergents as intended for them

Fig 2 Existing isolation signage intended for healthcare providers for all isolation categories (left) and for housekeeping personnel specific tocontact isolation (right) Legend These signs have been translated from German to English for publication

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 4 of 13

SaliencyThe existing signage for HCPs was placed next to or dir-ectly on the door of patients in single rooms togetherwith an isolation cart with all necessary protective mate-rials (eg gloves gowns masks) The isolation signagewas often one of many posted signs and HCPs reportedthat the colours were not salient relative to other sign-age meaning that the signs frequently went unnoticedOn intensive care units with patient bays rather thansingle rooms signage was attached to isolation carts po-sitioned near to the patient space When the isolationsignage was attached to the isolation cart HCPs re-ported that it did not provide a salient visual cue be-cause of the low signal-to-noise ratio Interviewed HCPsshared that this resulted in them unknowingly enteringinto to spaces of isolated patients

Trade-off between simplicity and complexityThe existing signage for HCPs neither indicated the cat-egory of isolation nor the necessary precautions to betaken Observations of these signs in use revealed thatHCPs desired more point-of-care information and theyaccordingly developed ldquopatchesrdquo whereby they addedstickers or wrote directly on the existing signage to addmissing information such as the category of isolation(Fig 3) Alternatively a simplifying ldquopatchrdquo had alsobeen applied to the detailed housekeeping signsWhereas the original sign indicated that a surgical maskldquomay be necessaryrdquo and that this should be discussedwith nursing personnel the patch saying ldquowith maskrdquo re-moved ambiguity and explicitly indicated the need todon a mask when cleaning the rooms of patients withnorovirus (Fig 4)

Method ambiguityWhile some HCPs were able to cite the personal pro-tective equipment (ie mask gown) necessary for eachcategory of isolation many were unsure about the orderwith which these should be donned and doffed andwhen hand hygiene should be performed when enteringand exiting the patient room

PersonasFollowing interviews and observations five personaswere established to embody the identified goals andneeds of key users of the signage system and to guidethe rest of the design process (Table 1) These personaswere printed and referred to throughout the subsequentstudy phases to keep a user-centred focus and to remindthe design team and participating HCPs about the rangeof user needs to be considered

List of design requirementsThe information gathered during interviews and observa-tions were used to establish a list of functional and non-functional design requirements (Table 2) Additional designrequirements were subsequently added to this evolvingdocument throughout the design process The functionalrequirements primarily concerned information that thesignage should provide to different categories of personneland visitors are alerted and informed about the necessaryisolation precautions The non-functional requirementsconcerned the aspects of the signage that are required tomake it compatible with the overall environment to whichit will be introduced as well as non-functional requirementson the system level that needed to be addressed for thesignage system to function optimally One such require-ment is that the signage must be consistent with corporatedesign guidelines at the USZ which indicate the coloursand fonts that should be used for internal and externalcommunication

Designing alternatives ndash design thinking workshopsTwo ideation workshops were conducted Several recur-ring themes were identified as discussed in the followingsections

Forcing functionSeveral workshop participants presented ideas that em-ploy the engineering concept of forcing function abehaviour-shaping constraint in order to ensure compli-ance with isolation precautions During one workshopparticipants working on the problem statement ldquohowmight we ensure that required isolation measures arerespected 100 of the timerdquo ideated around forcingfunction solutions to detect if appropriate personalprotective equipment had been donned prior to openingthe patient door (Fig 5) Due to safety and feasibility

Fig 3 Existing signage for healthcare providers with ldquopatchrdquo toindicate category of isolation Legend This ldquopatchrdquo introduced byhealthcare providers demonstrates that the existing signage was notoffering sufficient information and that healthcare providers wantedthe signage to indicate the category of isolation The patchindicated with an arrow reads ldquocontact isolationrdquo

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 5 of 13

concerns with this idea during the prototyping phasethese participants instead employed masks suspended inthe doorway through which healthcare providers mustwalk thereby automatically donning a mask upon roomentry Such solutions must be assessed to ensure theirsafety prior to introduction Employing such forcingfunctions would address issues of forgetting which par-ticipants confirmed is one of the main reasons for pro-cedural noncompliance

Not ldquobreaking the flow of workrdquoSeveral participants expressed that a major barrier tocompliance with isolation precautions is the time neces-sary to find out which precautions are applicable and lo-cate and don the materials necessary for complianceThis was expressed in the problem statement ldquohowmight we save time while respecting isolation precau-tionsrdquo Participants proposed multiple solutions Indicat-ing on the signage both the type of isolation as well asthe necessary precautions eliminates the cognitive loadrequired for those entering the room and saves time ne-cessary to identify the relevant guidelines and materialsFigure 6 demonstrates both the ideation and prototypingof one such solution which sends a strong visual cue in-dicating the type of protective equipment that should beemployed

Placement of visual cuesAnother theme identified during the workshops was thatthe current provision of visual cues (only at the entranceto the patient room) is inadequate When prompted

about where visual cues should be located the majorityof participants indicated that some cues should also belocated inside the patient room The most commonlyproposed locations for visual cues included at the en-trance to the patient room at the foot of the patientbed and next to patient charts

Prototyping and evaluationSymbol development and judgement testDuring design thinking workshops participants gener-ated ideas and sketches about how to portray the threemain isolation categories (contact droplet and airborne)as symbols (Additional file 1) Variants of each isolationsymbol [contact isolation (n = 4) droplet isolation (n =5) and airborne isolation (n = 6)] were then designedemploying the same themes that emerged from the par-ticipants themselves in order to be consistent with usermental models and thus increase comprehension Re-spondentsrsquo judgements of how many of their colleagueswould understand the symbols ranged from 17 to 78(Additional file 2) Of note the variants that picturedtwo whole human figures performed better in judgementtesting than those without the human figure or part ofthe human body (eg only hands) The highest rated var-iants of each symbol were retained and further examinedthrough a comprehensibility test

Symbol comprehensibility testDetailed results of the comprehensibility testing can befound in Additional file 2 Whereas the symbols for con-tact and droplet isolation were correctly understood by a

Fig 4 Existing signage for housekeeping (left) with ldquopatchrdquo to clarify ambiguous mask indication (right) Legend This ldquopatchrdquo introduced byhousekeeping personnel suggests that the existing signage provided ambiguous instructions and that they preferred a more simple instructionto don a mask The patch indicated with an arrow reads ldquowith maskrdquo instead of ldquosurgical mask if necessaryrdquo The existing signage (left) wastranslated from German to English for publication

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 6 of 13

Table 1 Established personas

Persona Description User requirements

Julia Internal Medicine NurseAge 25

bull Julia began working in the internal medicine ward atthe USZ directly after finishing her nursing degreeHaving freshly finished her schooling she looks up tothe more experienced nurses

bull She is especially vigilant in her infection controlpractices including isolation precautions as this was amajor focus of her training

bull When she is not sure about which isolation precautionsshe should use for a patient she (erroneously)references the sign on the housekeeping cart

bull Signage should offer multiple levels of information forfrequent versus rare users For example recognition ofthe standardised signage colour may be enough forfrequent users to recall the necessary precautionswhereas rare users need to be reminded of the specificprecautions

bull Target audience must be clearly distinguishable

Sarah Nursing assistantAge 48

bull Sarah has worked in several wards of the USZ One ofthe highlights of her job is that it allows her to have aclose relationship with patients

bull She has a hard time bringing up isolation with herpatients because she sympathises with the emotionaleffects this may have For the same reason shesometimes neglects to respect hygiene measures suchas hand hygiene and wearing gowns as she feels thisputs a separation between herself and the patient

bull Signage should aim to establish social norms increaseacceptability of performing infection preventionmeasures

Paul Emergency WardPhysician Age 42

bull During medical school in Germany Paul chose tospecialise in emergency medicine because Dr Housewas his favourite TV drama and he enjoys the challengeand rush to resolve critical situations

bull Paulrsquos career took off quickly after he successfullypublished a highly cited paper in New England Journalof Medicine and he became known as an expert influid management in poly-trauma patients

bull In the rush of acute care situations infection controlmeasures sometimes take a back seat but no one daresto correct this senior physician

bull Signage must quickly communicate essentialinformation and must not require extra time

bull Barriers to performing isolation precautions (egmissing materials) should be removed

bull Signage should aim to support psychological safety(eg speaking up)

Omar Porter Age 55 bull Prior to moving to Switzerland with his family five yearsago Omar was an elementary school teacher in TunisiaHe came to Switzerland with no prior Germanknowledge but was able to begin working in thehospital while simultaneously taking German classes

bull When he began working he relied on clear photos andsymbols to help him interpret written protocols

bull Signage must be able to communicate effectively withstaff for whom German is not a native language forexample with self-explanatory images

Teresa Housekeeping staffAge 46

bull Teresa is specially assigned to work in the emergencyward where they have specific cleaning andmaintenance procedures from the rest of the hospitalHer native language is Portuguese but her outgoingpersonality helped her to quickly learn German throughchatting with her colleagues when she began working

bull Signage content may need to be adapted for specificsettings

bull Signage must be able to communicate effectively withstaff for whom German is not a native language forexample with self-explanatory images

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 7 of 13

majority of participants the symbols for airborne isola-tion were sometimes incorrectly interpreted as meaningdroplet isolation The three variants with the highestcomprehensibility and least conflicting interpretationswere retained for use in further signage prototypes(Fig 7)

Iterative prototyping and evaluationThe process of iterative prototyping and evaluation of iso-lation signage occurred in parallel to the testing of sym-bols During this process several prototypes emerged withvarying levels of sophistication In the earliest stages ideaswere expressed on paper in the form of sketches Thosesketches with the most positive feedback from the targetpopulation were then transformed into more sophisticatedprototypes As prototypes were continually evaluatedthrough informal discussions with frontline HCPs theirfeedback provided insights that led to further refining ofconsecutive prototypes Experts in infection preventionand control were regularly consulted to ensure accuracyof the signage content This iterative design process asdocumented in Additional file 3 continued until satur-ation was achieved (ie until no new feedback was given)

Final signage solutionThe final solutions that resulted from the iterative proto-typing and evaluation process were shared with agraphic designer to produce the final signage system forthe three main isolation categories (Fig 8) as well as twosigns for combined precautions (Fig 9) This solutionfeatures a caution tape graphic and salient colours todraw attention to those entering the room that specialprecautions must be taken The isolation categories arecommunicated dually through the colour which is stan-dardised throughout all isolation precaution documentsand the prominent symbol portraying the transmissionpathway The specific precautions are portrayed in theorder in which they must be performed removing

method ambiguity The use of text is limited and thesignage relies largely on user-friendly graphics to sup-port comprehension regardless of language proficiencyThe signage is available for download on the intranetand can be printed with one sign per A4 sheet of paperBeyond the scope of the physical signage hospital guide-lines have also been introduced that limit the amountand type of information that can be posted on patientdoors which increases the saliency of remaining signageIn collaboration with the infection prevention depart-ment the housekeeping department has also revisedtheir isolation precaution guidelines and brochures toeliminate confusion with signage intended for HCPsThe signs were implemented by e-mailing heads of

wards to inform them of the new signage announce-ment and posting of the new signs on the intranet ser-ver and physically distributing printed signs to eachhospital ward according to number of beds Additionalcopies were made available for order Physical copiesand links to the previous signage were removed

DiscussionThis paper describes the successful application of a user-centred participatory design process to develop a sign-age system for communicating isolation precautionsThe resulting signage system aims to serve as a visualcue for HCPs remove ambiguity and elicit safe infectionprevention behaviours to ultimately prevent the trans-mission of infectious agentsOur analysis of existing isolation signage revealed that

ambiguity was indeed a major factor responsible fornon-compliance with transmission-based precautions inour hospital This is consistent with the findings ofGurses et al who propose systems ambiguity as aframework to explain procedural non-compliance inhealthcare [8] Ambiguity in our institution was identi-fied mainly in the form of task ambiguity (not knowingwhich guidelines are applicable for which patients) and

Table 1 Established personas (Continued)

Persona Description User requirements

at the USZ even picking up a Swiss German accentbull She has been working in the emergency ward for 12years now and although she has no medical trainingshe is excellent at what she does

Legend Personas fictional characters based on input from real users were established to understand the needs and goals of the individuals who will interactwith the signage system and to guide the subsequent design process

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 8 of 13

method ambiguity (not knowing how or in which orderto complete a particular guideline) This was due to thelack of indication about which category of isolation a pa-tient was under or which preventative measures wereapplicable To specifically address barriers related to taskand method ambiguity the new signage was designedwith the intent of bringing isolation guidelines directlyto the frontline where their use is indicated also re-ferred to as placing ldquoknowledge in the worldrdquo [23 24]The symbols and colour-scheme developed to portray

isolation categories (contact droplet and airborne) weredeemed to be an important part of the overall signagewith the intention that these may become standardisedthroughout the institution and thus increase recognitionand compliance The comprehensibility evaluation ofthese symbols revealed that the airborne and droplet iso-lation symbols were the most often confounded This isnot surprising due to the similar means by which bothairborne particles and droplets can be propelled into theenvironment through coughing and sneezing In orderto further distinguish these symbols they have beenassociated in the new signage with standardised colourscheme where airborne is blue droplet is green andcontact is orange The standardisation of these colourschemes is intended to further aid in the distinction ofdifferent isolation categories and make them quicklyrecognisable once they have been learned through re-peated exposure

Table 2 Identified design requirements

Functional requirements (what the system should do)

Informationdissemination

bull Draw the attention of anyone entering the room thatspecial precautions must be taken

bull Inform any person entering the patient room whatisolation status that patient has

bull Inform any person entering the patient room aboutthe isolation precautions they must employ accordingto the patientrsquos isolation status

Inform healthcare personnel about requiredpersonal protective equipment

Inform cleaning staff about required protectiveequipment adapted disinfectants and prioritisedcleaning measures

Inform visitors about required personal protectiveequipment or instruct them to see a staff member

bull Inform any person entering the room about the orderin which precautions (eg donning and doffingpersonal protective equipment hand hygiene) shouldbe performed

bull Inform anyone transporting the patient about thetransmission-based precautions that shouldbe respected

bull In addition to the three main categories oftransmission-based precautions (contact droplet andairborne) signage should also be designed tocommunicate combined or ldquolightrdquo isolationprecautions specific to the USZ

USZ guidelines bull Be consistent with USZ guidelines for isolationprecautions The three main isolationcategories include

Contact isolation don gown Droplet isolation don surgical mask Airborne isolation don FFP2 mask

bull Communicate combined isolation precautions Contact + Droplet isolation don gown andsurgical mask

Contact + Airborne isolation don gown andFFP2 mask

Non-functional requirements(constraints on the system and its development)

Maintenancerestraints

bull Must be easy to hang and remove on an as-need basisbull If printed on paper must either be laminate so that itmay be cleaned and reused or single use

Accessibilityandconfidentialityrequirements

bull Should include graphics and symbols to accommodatenon-native German speaking personnel

bull Signage should avoid potential patient stigmatisationand should not disclose any confidentialpatient information

bull Signage must be accessible to individuals with colourvision deficiency for example by avoiding problematiccolour combinations and employing both colours andsymbols to convey messages over multiple channels

Physicalenvironmentrequirements

bull Signage must be noticeable relative to other signs inthe healthcare setting(appropriate single-to-noise ratio)

bull Some indication of the patientrsquos isolation statusshould travel with the patient at all times so that theappropriate transmission-based precautions can becommunicated at all times (eg when the patient isoutside of the room where the sign is posted) ndash thiscould be attached to the patient herself or to thepatientrsquos bed

bull Signage for housekeeping personnel should be of aportable size (A4 or smaller) so that it can fit on thecleaning trolleys

Organisational bull The signage should be able to quickly communicate

Table 2 Identified design requirements (Continued)

environmentrequirements

the required actions so that healthcare providers donot need to slow down (lsquobreak the rhythmrsquo) tointerpret them

bull If sign will be paper-based it should be easilyaccessible to staff on the ward when an isolatedpatient arrives (eg printed copies from intranet)or purchasable

bull Any posted signs must be consistent with theCorporate Design Guidelines

bull Information communicated through signage must beconsistent with evidence based-guidelines such as theCDC 2007 guidance as well as institutional infectioncontrol guidelines

Technicalenvironmentrequirements

bull Colour printer must be available if units are to printtheir own copies of paper-based signage

bull Intranet connection must be available if units are todownload the signs

bull Staff must be able to post the signage either by usingan adhesive material or the signs may be printeddirectly onto an adhesive sheet

bull Handling of signage material should be cost-effectiveand practical in every-day use

bull It should be possible to update the signage systemeasily in case new hospital rulesguidelinesare introduced

Legend Design requirements identified during interviews and observationsserved as a guide to ensure that subsequent designs met user needs whilesatisfying functional and non-functional requirements USZ University HospitalZurich CDC Centers for Disease Control

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 9 of 13

It is commonly accepted that ldquoconcept-relatedrdquo sym-bols which are abstract representations of the referentor subject they represent require more training beforethey can be understood by viewers [25] However by de-signing symbols for isolation precaution signage suchthat they are consistent with mental models this projectaimed to achieve a design that requires minimal trainingand that may also be intuitively understood Interest-ingly comprehensibility testing revealed that symbolsshowing the whole human figure were rated higher thanthose without the human figure or with an abstract partof the human body (eg only hands) This finding is con-sistent with results of the Hablamos Juntos Report who

evaluated the usability of several symbols for use in way-finding signage in hospital settings and found that symbolswith the whole human body were best understood [12]In addition to comprehensibility benefits including

the human figure particularly human eyes may be im-portant as it relates to emotional design Multiple studieshave examined the effect of images of human eyes oncooperative behaviour such as an ldquohonour systemrdquomethod of payment to an honesty box to pay for drinksin a coffee room [26] Such studies have found that thepresence of eye images act as a subtle cue and thatpeople paid as much as three times more often for theirdrinks when human eyes were displayed as opposed to

Fig 5 Workshop example of ldquoforcing functionrdquo during ideation (left) and prototyping (right) phases Legend This extract from a design thinkingworkshop shows one participantrsquos proposal to use a ldquoforcing functionrdquo to ensure that hands are disinfected prior to entry The middle shows adoor handle that only opens when alcohol is detected The right shows a prototype featuring the forcing function of a mask suspended in thedoorway through which clinicians must walk and thereby don masks upon room entry

Fig 6 Idea (left) and Prototype (right) of signage from design thinking workshop Legend This prototype developed during a design thinkingworkshop sends a strong visual cue about the necessary precautions The sign reads ldquoWarning before entering helliprdquo

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 10 of 13

when a neutral control image was displayed [27] Studiesin infection prevention settings however have hadmixed success in reproducing this effect [28ndash30] Furtherstudies on this topic are warranted to better understandhow signage may be employed to prime cooperative be-haviour and thus improve guideline adherenceThe field of infection prevention and patient safety is

rife with opportunities to actively include HCPs in user-centred design processes to improve healthcare environ-ments and practises The participatory design approachwas well suited for this inquiry as it allowed us to activelyinvolve stakeholders with essential insights thereby estab-lishing ownership and increasing chances of acceptanceand sustainability of the new signage The benefits of col-laborating with frontline HCPs extend beyond the scopeof the resulting design to also improve the image of theInfection Control department as a resource and to nurturethe possibility of further collaboration Recent reviews onthe use of participatory approaches such as experience-based co-design or co-production in which patients andhealthcare staff are engaged to improve health servicesreport outcomes related to the value of patient and staffinvolvement the quantity and quality of ideas and sugges-tions to modify practices and tangible changes in servicedelivery and user experience [31 32]Some limitations of this study should be considered

During this study we were faced with the challenge of

changing institutional guidelines for isolation precau-tions This prevented a quantitative analysis of change inpractice and presented a challenge during the evaluationwith frontline staff who were not yet familiar with thenew guidelines and thus had a tendency to focus on thediscrepancies between the ldquonewrdquo vs the current guide-lines rather than signage design The latter was ad-dressed through discussion with participants about thepossibility of new evidence-based practices and also bypresenting frontline users with prototypes that were con-sistent with their existing mental models ie consistentwith current guidelines Also the introduction of suchsignage is intended to serve as a visual cue and to re-move ambiguity regarding which precautions should beused and when The introduction of such signage how-ever does not entirely remove other known barriers tocompliance with isolation precautions such as ldquolack oftimerdquo [33] or ldquoavailability of protective clothingrdquo [5] It isthus imperative that the introduction of such signagetakes place within the context of a systems approach en-suring for example that the necessary time and materialresources are also available in order to mitigate thesebarriers

ConclusionsIn conclusion this study resulted in a user-centred sign-age design solution and set of comprehensible symbols

Fig 7 Symbols for contact (left) droplet (middle) and airborne (right) isolation Legend The variants of each symbol with the highest judgementand comprehensibility ratings were retained for use in further signage development phases

Fig 8 The final signage solution for contact (left) droplet (middle) and airborne (right) isolation Legend The final solution to be printed withone sign per A4 sheet incorporates several features to satisfy the identified design requirements These signs have been translated from Germanto English for publication

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 11 of 13

to remove ambiguity and to make compliance withevidence-based guidelines easy and intuitive for HCPsand visitors to the USZ The introduction of signageparticularly for infection control offers a promising op-portunity to make guidelines available directly at thefrontline where their use is indicated thereby reducingthe need for training and standard operating proceduresThis article further describes the application of a user-centred participatory design process which has great po-tential for application in the field of hospital infectioncontrol to design solutions that make performing infec-tion prevention behaviours easy and intuitive

Supplementary informationSupplementary information accompanies this paper at httpsdoiorg101186s13756-019-0629-9

Additional file 1 Pictorial portrayal of isolation categories

Additional file 2 Results of Judgement and Comprehension testing

Additional file 3 Iterations of Isolation Signage System

AbbreviationsCDC Centers for Disease Control HAI Healthcare-associated infectionsHCP Healthcare provider ID Infectious diseases IPC Infection preventionand control USZ University Hospital Zurich

AcknowledgementsWe would like to warmly acknowledge all study participants We would alsolike to acknowledge Andreacute Rothfuchs of Studio Sirup who provided graphicdesign services for the final signage solution

Authorsrsquo contributionsLC and HS conceived and designed the study LC conducted data collectionanalysis and iterative signage design and evaluation MS MM and AWprovided iterative feedback to inform the final signage solution LC draftedthe manuscript and all authors provided detailed feedback and approvedthe final manuscript

FundingThis work was partially funded by the Swiss National Science Foundation(32003B_149474) and by the University Hospital of Zurich Department ofQuality Management and Patient Safety

Availability of data and materialsThe datasets used andor analysed during the current study are availablefrom the corresponding author on reasonable request

Ethics approval and consent to participateThe Zurich Cantonal Ethics Committee waived the need for formal ethicsreview of this project (KEK-StV-Nr 4114) Participation in all study activitieswas voluntary and participants were free to withdraw at any time Allinterview and workshop participants provided written informed consentprior to participation

Consent for publicationNot applicable

Competing interestsThe authors declare that they have no competing interests

Author details1Division of Infectious Diseases and Hospital Epidemiology UniversityHospital Zurich and University of Zurich Raemistrasse 100 HAL14 8091Zurich Switzerland 2Department of Management Technology andEconomics ETH Zurich Zurich Switzerland

Received 9 August 2019 Accepted 16 October 2019

References1 World Health Organization (WHO) Report on the burden of endemic health

care-associated infection wordwide Geneva World Health Organization2011

2 Siegel JD Rhinehard E Jackson M et al 2007 guideline for isolationprecautions preventing transmission of infectious agents in healthcaresettings 2007

3 Larson E Kretzer EK Compliance with handwashing and barrier precautionsJ Hosp Infect 199530(Suppl)88ndash106

4 Weber D Sickbert-Bennett EE Brown VM et al Compliance withisolation precautions at a university hospital Infect Control HospEpidemiol 200728358ndash61

5 Gammon J Morgan-Samuel H Gould D A review of the evidence forsuboptimal compliance of healthcare practitioners to standarduniversalinfection control precautions J Clin Nurs 200817157ndash67 httpsdoiorg101111j1365-2702200601852x

6 Sax H Perneger T Hugonnet S et al Knowledge of standard and isolationprecautions in a large teaching hospital Infect Control Hosp Epidemiol200526298ndash304 httpsdoiorg101086502543

7 Sax H Uckay I Richet H et al Determinants of good adherence to handhygiene among healthcare workers who have extensive exposure to handhygiene campaigns Infect Control Hosp Epidemiol 2007281267ndash74httpsdoiorg101086521663

8 Gurses AP Seidl KL Vaidya V et al Systems ambiguity and guidelinecompliance a qualitative study of how intensive care units follow evidence-based guidelines to reduce healthcare-associated infections Qual Saf HealthCare 200817351ndash9 httpsdoiorg101136qshc2006021709

9 Grundgeiger T Sanderson PM Orihuela CB et al Prospective memoryin the ICU the effect of visual cues on task execution in arepresentative simulation Ergonomics 201356579ndash89 httpsdoiorg101080001401392013765604

Fig 9 The final signage solution for combined precautions Legend These signs have been translated from German to English for publication

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 12 of 13

SaliencyThe existing signage for HCPs was placed next to or dir-ectly on the door of patients in single rooms togetherwith an isolation cart with all necessary protective mate-rials (eg gloves gowns masks) The isolation signagewas often one of many posted signs and HCPs reportedthat the colours were not salient relative to other sign-age meaning that the signs frequently went unnoticedOn intensive care units with patient bays rather thansingle rooms signage was attached to isolation carts po-sitioned near to the patient space When the isolationsignage was attached to the isolation cart HCPs re-ported that it did not provide a salient visual cue be-cause of the low signal-to-noise ratio Interviewed HCPsshared that this resulted in them unknowingly enteringinto to spaces of isolated patients

Trade-off between simplicity and complexityThe existing signage for HCPs neither indicated the cat-egory of isolation nor the necessary precautions to betaken Observations of these signs in use revealed thatHCPs desired more point-of-care information and theyaccordingly developed ldquopatchesrdquo whereby they addedstickers or wrote directly on the existing signage to addmissing information such as the category of isolation(Fig 3) Alternatively a simplifying ldquopatchrdquo had alsobeen applied to the detailed housekeeping signsWhereas the original sign indicated that a surgical maskldquomay be necessaryrdquo and that this should be discussedwith nursing personnel the patch saying ldquowith maskrdquo re-moved ambiguity and explicitly indicated the need todon a mask when cleaning the rooms of patients withnorovirus (Fig 4)

Method ambiguityWhile some HCPs were able to cite the personal pro-tective equipment (ie mask gown) necessary for eachcategory of isolation many were unsure about the orderwith which these should be donned and doffed andwhen hand hygiene should be performed when enteringand exiting the patient room

PersonasFollowing interviews and observations five personaswere established to embody the identified goals andneeds of key users of the signage system and to guidethe rest of the design process (Table 1) These personaswere printed and referred to throughout the subsequentstudy phases to keep a user-centred focus and to remindthe design team and participating HCPs about the rangeof user needs to be considered

List of design requirementsThe information gathered during interviews and observa-tions were used to establish a list of functional and non-functional design requirements (Table 2) Additional designrequirements were subsequently added to this evolvingdocument throughout the design process The functionalrequirements primarily concerned information that thesignage should provide to different categories of personneland visitors are alerted and informed about the necessaryisolation precautions The non-functional requirementsconcerned the aspects of the signage that are required tomake it compatible with the overall environment to whichit will be introduced as well as non-functional requirementson the system level that needed to be addressed for thesignage system to function optimally One such require-ment is that the signage must be consistent with corporatedesign guidelines at the USZ which indicate the coloursand fonts that should be used for internal and externalcommunication

Designing alternatives ndash design thinking workshopsTwo ideation workshops were conducted Several recur-ring themes were identified as discussed in the followingsections

Forcing functionSeveral workshop participants presented ideas that em-ploy the engineering concept of forcing function abehaviour-shaping constraint in order to ensure compli-ance with isolation precautions During one workshopparticipants working on the problem statement ldquohowmight we ensure that required isolation measures arerespected 100 of the timerdquo ideated around forcingfunction solutions to detect if appropriate personalprotective equipment had been donned prior to openingthe patient door (Fig 5) Due to safety and feasibility

Fig 3 Existing signage for healthcare providers with ldquopatchrdquo toindicate category of isolation Legend This ldquopatchrdquo introduced byhealthcare providers demonstrates that the existing signage was notoffering sufficient information and that healthcare providers wantedthe signage to indicate the category of isolation The patchindicated with an arrow reads ldquocontact isolationrdquo

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 5 of 13

concerns with this idea during the prototyping phasethese participants instead employed masks suspended inthe doorway through which healthcare providers mustwalk thereby automatically donning a mask upon roomentry Such solutions must be assessed to ensure theirsafety prior to introduction Employing such forcingfunctions would address issues of forgetting which par-ticipants confirmed is one of the main reasons for pro-cedural noncompliance

Not ldquobreaking the flow of workrdquoSeveral participants expressed that a major barrier tocompliance with isolation precautions is the time neces-sary to find out which precautions are applicable and lo-cate and don the materials necessary for complianceThis was expressed in the problem statement ldquohowmight we save time while respecting isolation precau-tionsrdquo Participants proposed multiple solutions Indicat-ing on the signage both the type of isolation as well asthe necessary precautions eliminates the cognitive loadrequired for those entering the room and saves time ne-cessary to identify the relevant guidelines and materialsFigure 6 demonstrates both the ideation and prototypingof one such solution which sends a strong visual cue in-dicating the type of protective equipment that should beemployed

Placement of visual cuesAnother theme identified during the workshops was thatthe current provision of visual cues (only at the entranceto the patient room) is inadequate When prompted

about where visual cues should be located the majorityof participants indicated that some cues should also belocated inside the patient room The most commonlyproposed locations for visual cues included at the en-trance to the patient room at the foot of the patientbed and next to patient charts

Prototyping and evaluationSymbol development and judgement testDuring design thinking workshops participants gener-ated ideas and sketches about how to portray the threemain isolation categories (contact droplet and airborne)as symbols (Additional file 1) Variants of each isolationsymbol [contact isolation (n = 4) droplet isolation (n =5) and airborne isolation (n = 6)] were then designedemploying the same themes that emerged from the par-ticipants themselves in order to be consistent with usermental models and thus increase comprehension Re-spondentsrsquo judgements of how many of their colleagueswould understand the symbols ranged from 17 to 78(Additional file 2) Of note the variants that picturedtwo whole human figures performed better in judgementtesting than those without the human figure or part ofthe human body (eg only hands) The highest rated var-iants of each symbol were retained and further examinedthrough a comprehensibility test

Symbol comprehensibility testDetailed results of the comprehensibility testing can befound in Additional file 2 Whereas the symbols for con-tact and droplet isolation were correctly understood by a

Fig 4 Existing signage for housekeeping (left) with ldquopatchrdquo to clarify ambiguous mask indication (right) Legend This ldquopatchrdquo introduced byhousekeeping personnel suggests that the existing signage provided ambiguous instructions and that they preferred a more simple instructionto don a mask The patch indicated with an arrow reads ldquowith maskrdquo instead of ldquosurgical mask if necessaryrdquo The existing signage (left) wastranslated from German to English for publication

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 6 of 13

Table 1 Established personas

Persona Description User requirements

Julia Internal Medicine NurseAge 25

bull Julia began working in the internal medicine ward atthe USZ directly after finishing her nursing degreeHaving freshly finished her schooling she looks up tothe more experienced nurses

bull She is especially vigilant in her infection controlpractices including isolation precautions as this was amajor focus of her training

bull When she is not sure about which isolation precautionsshe should use for a patient she (erroneously)references the sign on the housekeeping cart

bull Signage should offer multiple levels of information forfrequent versus rare users For example recognition ofthe standardised signage colour may be enough forfrequent users to recall the necessary precautionswhereas rare users need to be reminded of the specificprecautions

bull Target audience must be clearly distinguishable

Sarah Nursing assistantAge 48

bull Sarah has worked in several wards of the USZ One ofthe highlights of her job is that it allows her to have aclose relationship with patients

bull She has a hard time bringing up isolation with herpatients because she sympathises with the emotionaleffects this may have For the same reason shesometimes neglects to respect hygiene measures suchas hand hygiene and wearing gowns as she feels thisputs a separation between herself and the patient

bull Signage should aim to establish social norms increaseacceptability of performing infection preventionmeasures

Paul Emergency WardPhysician Age 42

bull During medical school in Germany Paul chose tospecialise in emergency medicine because Dr Housewas his favourite TV drama and he enjoys the challengeand rush to resolve critical situations

bull Paulrsquos career took off quickly after he successfullypublished a highly cited paper in New England Journalof Medicine and he became known as an expert influid management in poly-trauma patients

bull In the rush of acute care situations infection controlmeasures sometimes take a back seat but no one daresto correct this senior physician

bull Signage must quickly communicate essentialinformation and must not require extra time

bull Barriers to performing isolation precautions (egmissing materials) should be removed

bull Signage should aim to support psychological safety(eg speaking up)

Omar Porter Age 55 bull Prior to moving to Switzerland with his family five yearsago Omar was an elementary school teacher in TunisiaHe came to Switzerland with no prior Germanknowledge but was able to begin working in thehospital while simultaneously taking German classes

bull When he began working he relied on clear photos andsymbols to help him interpret written protocols

bull Signage must be able to communicate effectively withstaff for whom German is not a native language forexample with self-explanatory images

Teresa Housekeeping staffAge 46

bull Teresa is specially assigned to work in the emergencyward where they have specific cleaning andmaintenance procedures from the rest of the hospitalHer native language is Portuguese but her outgoingpersonality helped her to quickly learn German throughchatting with her colleagues when she began working

bull Signage content may need to be adapted for specificsettings

bull Signage must be able to communicate effectively withstaff for whom German is not a native language forexample with self-explanatory images

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 7 of 13

majority of participants the symbols for airborne isola-tion were sometimes incorrectly interpreted as meaningdroplet isolation The three variants with the highestcomprehensibility and least conflicting interpretationswere retained for use in further signage prototypes(Fig 7)

Iterative prototyping and evaluationThe process of iterative prototyping and evaluation of iso-lation signage occurred in parallel to the testing of sym-bols During this process several prototypes emerged withvarying levels of sophistication In the earliest stages ideaswere expressed on paper in the form of sketches Thosesketches with the most positive feedback from the targetpopulation were then transformed into more sophisticatedprototypes As prototypes were continually evaluatedthrough informal discussions with frontline HCPs theirfeedback provided insights that led to further refining ofconsecutive prototypes Experts in infection preventionand control were regularly consulted to ensure accuracyof the signage content This iterative design process asdocumented in Additional file 3 continued until satur-ation was achieved (ie until no new feedback was given)

Final signage solutionThe final solutions that resulted from the iterative proto-typing and evaluation process were shared with agraphic designer to produce the final signage system forthe three main isolation categories (Fig 8) as well as twosigns for combined precautions (Fig 9) This solutionfeatures a caution tape graphic and salient colours todraw attention to those entering the room that specialprecautions must be taken The isolation categories arecommunicated dually through the colour which is stan-dardised throughout all isolation precaution documentsand the prominent symbol portraying the transmissionpathway The specific precautions are portrayed in theorder in which they must be performed removing

method ambiguity The use of text is limited and thesignage relies largely on user-friendly graphics to sup-port comprehension regardless of language proficiencyThe signage is available for download on the intranetand can be printed with one sign per A4 sheet of paperBeyond the scope of the physical signage hospital guide-lines have also been introduced that limit the amountand type of information that can be posted on patientdoors which increases the saliency of remaining signageIn collaboration with the infection prevention depart-ment the housekeeping department has also revisedtheir isolation precaution guidelines and brochures toeliminate confusion with signage intended for HCPsThe signs were implemented by e-mailing heads of

wards to inform them of the new signage announce-ment and posting of the new signs on the intranet ser-ver and physically distributing printed signs to eachhospital ward according to number of beds Additionalcopies were made available for order Physical copiesand links to the previous signage were removed

DiscussionThis paper describes the successful application of a user-centred participatory design process to develop a sign-age system for communicating isolation precautionsThe resulting signage system aims to serve as a visualcue for HCPs remove ambiguity and elicit safe infectionprevention behaviours to ultimately prevent the trans-mission of infectious agentsOur analysis of existing isolation signage revealed that

ambiguity was indeed a major factor responsible fornon-compliance with transmission-based precautions inour hospital This is consistent with the findings ofGurses et al who propose systems ambiguity as aframework to explain procedural non-compliance inhealthcare [8] Ambiguity in our institution was identi-fied mainly in the form of task ambiguity (not knowingwhich guidelines are applicable for which patients) and

Table 1 Established personas (Continued)

Persona Description User requirements

at the USZ even picking up a Swiss German accentbull She has been working in the emergency ward for 12years now and although she has no medical trainingshe is excellent at what she does

Legend Personas fictional characters based on input from real users were established to understand the needs and goals of the individuals who will interactwith the signage system and to guide the subsequent design process

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 8 of 13

method ambiguity (not knowing how or in which orderto complete a particular guideline) This was due to thelack of indication about which category of isolation a pa-tient was under or which preventative measures wereapplicable To specifically address barriers related to taskand method ambiguity the new signage was designedwith the intent of bringing isolation guidelines directlyto the frontline where their use is indicated also re-ferred to as placing ldquoknowledge in the worldrdquo [23 24]The symbols and colour-scheme developed to portray

isolation categories (contact droplet and airborne) weredeemed to be an important part of the overall signagewith the intention that these may become standardisedthroughout the institution and thus increase recognitionand compliance The comprehensibility evaluation ofthese symbols revealed that the airborne and droplet iso-lation symbols were the most often confounded This isnot surprising due to the similar means by which bothairborne particles and droplets can be propelled into theenvironment through coughing and sneezing In orderto further distinguish these symbols they have beenassociated in the new signage with standardised colourscheme where airborne is blue droplet is green andcontact is orange The standardisation of these colourschemes is intended to further aid in the distinction ofdifferent isolation categories and make them quicklyrecognisable once they have been learned through re-peated exposure

Table 2 Identified design requirements

Functional requirements (what the system should do)

Informationdissemination

bull Draw the attention of anyone entering the room thatspecial precautions must be taken

bull Inform any person entering the patient room whatisolation status that patient has

bull Inform any person entering the patient room aboutthe isolation precautions they must employ accordingto the patientrsquos isolation status

Inform healthcare personnel about requiredpersonal protective equipment

Inform cleaning staff about required protectiveequipment adapted disinfectants and prioritisedcleaning measures

Inform visitors about required personal protectiveequipment or instruct them to see a staff member

bull Inform any person entering the room about the orderin which precautions (eg donning and doffingpersonal protective equipment hand hygiene) shouldbe performed

bull Inform anyone transporting the patient about thetransmission-based precautions that shouldbe respected

bull In addition to the three main categories oftransmission-based precautions (contact droplet andairborne) signage should also be designed tocommunicate combined or ldquolightrdquo isolationprecautions specific to the USZ

USZ guidelines bull Be consistent with USZ guidelines for isolationprecautions The three main isolationcategories include

Contact isolation don gown Droplet isolation don surgical mask Airborne isolation don FFP2 mask

bull Communicate combined isolation precautions Contact + Droplet isolation don gown andsurgical mask

Contact + Airborne isolation don gown andFFP2 mask

Non-functional requirements(constraints on the system and its development)

Maintenancerestraints

bull Must be easy to hang and remove on an as-need basisbull If printed on paper must either be laminate so that itmay be cleaned and reused or single use

Accessibilityandconfidentialityrequirements

bull Should include graphics and symbols to accommodatenon-native German speaking personnel

bull Signage should avoid potential patient stigmatisationand should not disclose any confidentialpatient information

bull Signage must be accessible to individuals with colourvision deficiency for example by avoiding problematiccolour combinations and employing both colours andsymbols to convey messages over multiple channels

Physicalenvironmentrequirements

bull Signage must be noticeable relative to other signs inthe healthcare setting(appropriate single-to-noise ratio)

bull Some indication of the patientrsquos isolation statusshould travel with the patient at all times so that theappropriate transmission-based precautions can becommunicated at all times (eg when the patient isoutside of the room where the sign is posted) ndash thiscould be attached to the patient herself or to thepatientrsquos bed

bull Signage for housekeeping personnel should be of aportable size (A4 or smaller) so that it can fit on thecleaning trolleys

Organisational bull The signage should be able to quickly communicate

Table 2 Identified design requirements (Continued)

environmentrequirements

the required actions so that healthcare providers donot need to slow down (lsquobreak the rhythmrsquo) tointerpret them

bull If sign will be paper-based it should be easilyaccessible to staff on the ward when an isolatedpatient arrives (eg printed copies from intranet)or purchasable

bull Any posted signs must be consistent with theCorporate Design Guidelines

bull Information communicated through signage must beconsistent with evidence based-guidelines such as theCDC 2007 guidance as well as institutional infectioncontrol guidelines

Technicalenvironmentrequirements

bull Colour printer must be available if units are to printtheir own copies of paper-based signage

bull Intranet connection must be available if units are todownload the signs

bull Staff must be able to post the signage either by usingan adhesive material or the signs may be printeddirectly onto an adhesive sheet

bull Handling of signage material should be cost-effectiveand practical in every-day use

bull It should be possible to update the signage systemeasily in case new hospital rulesguidelinesare introduced

Legend Design requirements identified during interviews and observationsserved as a guide to ensure that subsequent designs met user needs whilesatisfying functional and non-functional requirements USZ University HospitalZurich CDC Centers for Disease Control

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 9 of 13

It is commonly accepted that ldquoconcept-relatedrdquo sym-bols which are abstract representations of the referentor subject they represent require more training beforethey can be understood by viewers [25] However by de-signing symbols for isolation precaution signage suchthat they are consistent with mental models this projectaimed to achieve a design that requires minimal trainingand that may also be intuitively understood Interest-ingly comprehensibility testing revealed that symbolsshowing the whole human figure were rated higher thanthose without the human figure or with an abstract partof the human body (eg only hands) This finding is con-sistent with results of the Hablamos Juntos Report who

evaluated the usability of several symbols for use in way-finding signage in hospital settings and found that symbolswith the whole human body were best understood [12]In addition to comprehensibility benefits including

the human figure particularly human eyes may be im-portant as it relates to emotional design Multiple studieshave examined the effect of images of human eyes oncooperative behaviour such as an ldquohonour systemrdquomethod of payment to an honesty box to pay for drinksin a coffee room [26] Such studies have found that thepresence of eye images act as a subtle cue and thatpeople paid as much as three times more often for theirdrinks when human eyes were displayed as opposed to

Fig 5 Workshop example of ldquoforcing functionrdquo during ideation (left) and prototyping (right) phases Legend This extract from a design thinkingworkshop shows one participantrsquos proposal to use a ldquoforcing functionrdquo to ensure that hands are disinfected prior to entry The middle shows adoor handle that only opens when alcohol is detected The right shows a prototype featuring the forcing function of a mask suspended in thedoorway through which clinicians must walk and thereby don masks upon room entry

Fig 6 Idea (left) and Prototype (right) of signage from design thinking workshop Legend This prototype developed during a design thinkingworkshop sends a strong visual cue about the necessary precautions The sign reads ldquoWarning before entering helliprdquo

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 10 of 13

when a neutral control image was displayed [27] Studiesin infection prevention settings however have hadmixed success in reproducing this effect [28ndash30] Furtherstudies on this topic are warranted to better understandhow signage may be employed to prime cooperative be-haviour and thus improve guideline adherenceThe field of infection prevention and patient safety is

rife with opportunities to actively include HCPs in user-centred design processes to improve healthcare environ-ments and practises The participatory design approachwas well suited for this inquiry as it allowed us to activelyinvolve stakeholders with essential insights thereby estab-lishing ownership and increasing chances of acceptanceand sustainability of the new signage The benefits of col-laborating with frontline HCPs extend beyond the scopeof the resulting design to also improve the image of theInfection Control department as a resource and to nurturethe possibility of further collaboration Recent reviews onthe use of participatory approaches such as experience-based co-design or co-production in which patients andhealthcare staff are engaged to improve health servicesreport outcomes related to the value of patient and staffinvolvement the quantity and quality of ideas and sugges-tions to modify practices and tangible changes in servicedelivery and user experience [31 32]Some limitations of this study should be considered

During this study we were faced with the challenge of

changing institutional guidelines for isolation precau-tions This prevented a quantitative analysis of change inpractice and presented a challenge during the evaluationwith frontline staff who were not yet familiar with thenew guidelines and thus had a tendency to focus on thediscrepancies between the ldquonewrdquo vs the current guide-lines rather than signage design The latter was ad-dressed through discussion with participants about thepossibility of new evidence-based practices and also bypresenting frontline users with prototypes that were con-sistent with their existing mental models ie consistentwith current guidelines Also the introduction of suchsignage is intended to serve as a visual cue and to re-move ambiguity regarding which precautions should beused and when The introduction of such signage how-ever does not entirely remove other known barriers tocompliance with isolation precautions such as ldquolack oftimerdquo [33] or ldquoavailability of protective clothingrdquo [5] It isthus imperative that the introduction of such signagetakes place within the context of a systems approach en-suring for example that the necessary time and materialresources are also available in order to mitigate thesebarriers

ConclusionsIn conclusion this study resulted in a user-centred sign-age design solution and set of comprehensible symbols

Fig 7 Symbols for contact (left) droplet (middle) and airborne (right) isolation Legend The variants of each symbol with the highest judgementand comprehensibility ratings were retained for use in further signage development phases

Fig 8 The final signage solution for contact (left) droplet (middle) and airborne (right) isolation Legend The final solution to be printed withone sign per A4 sheet incorporates several features to satisfy the identified design requirements These signs have been translated from Germanto English for publication

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 11 of 13

to remove ambiguity and to make compliance withevidence-based guidelines easy and intuitive for HCPsand visitors to the USZ The introduction of signageparticularly for infection control offers a promising op-portunity to make guidelines available directly at thefrontline where their use is indicated thereby reducingthe need for training and standard operating proceduresThis article further describes the application of a user-centred participatory design process which has great po-tential for application in the field of hospital infectioncontrol to design solutions that make performing infec-tion prevention behaviours easy and intuitive

Supplementary informationSupplementary information accompanies this paper at httpsdoiorg101186s13756-019-0629-9

Additional file 1 Pictorial portrayal of isolation categories

Additional file 2 Results of Judgement and Comprehension testing

Additional file 3 Iterations of Isolation Signage System

AbbreviationsCDC Centers for Disease Control HAI Healthcare-associated infectionsHCP Healthcare provider ID Infectious diseases IPC Infection preventionand control USZ University Hospital Zurich

AcknowledgementsWe would like to warmly acknowledge all study participants We would alsolike to acknowledge Andreacute Rothfuchs of Studio Sirup who provided graphicdesign services for the final signage solution

Authorsrsquo contributionsLC and HS conceived and designed the study LC conducted data collectionanalysis and iterative signage design and evaluation MS MM and AWprovided iterative feedback to inform the final signage solution LC draftedthe manuscript and all authors provided detailed feedback and approvedthe final manuscript

FundingThis work was partially funded by the Swiss National Science Foundation(32003B_149474) and by the University Hospital of Zurich Department ofQuality Management and Patient Safety

Availability of data and materialsThe datasets used andor analysed during the current study are availablefrom the corresponding author on reasonable request

Ethics approval and consent to participateThe Zurich Cantonal Ethics Committee waived the need for formal ethicsreview of this project (KEK-StV-Nr 4114) Participation in all study activitieswas voluntary and participants were free to withdraw at any time Allinterview and workshop participants provided written informed consentprior to participation

Consent for publicationNot applicable

Competing interestsThe authors declare that they have no competing interests

Author details1Division of Infectious Diseases and Hospital Epidemiology UniversityHospital Zurich and University of Zurich Raemistrasse 100 HAL14 8091Zurich Switzerland 2Department of Management Technology andEconomics ETH Zurich Zurich Switzerland

Received 9 August 2019 Accepted 16 October 2019

References1 World Health Organization (WHO) Report on the burden of endemic health

care-associated infection wordwide Geneva World Health Organization2011

2 Siegel JD Rhinehard E Jackson M et al 2007 guideline for isolationprecautions preventing transmission of infectious agents in healthcaresettings 2007

3 Larson E Kretzer EK Compliance with handwashing and barrier precautionsJ Hosp Infect 199530(Suppl)88ndash106

4 Weber D Sickbert-Bennett EE Brown VM et al Compliance withisolation precautions at a university hospital Infect Control HospEpidemiol 200728358ndash61

5 Gammon J Morgan-Samuel H Gould D A review of the evidence forsuboptimal compliance of healthcare practitioners to standarduniversalinfection control precautions J Clin Nurs 200817157ndash67 httpsdoiorg101111j1365-2702200601852x

6 Sax H Perneger T Hugonnet S et al Knowledge of standard and isolationprecautions in a large teaching hospital Infect Control Hosp Epidemiol200526298ndash304 httpsdoiorg101086502543

7 Sax H Uckay I Richet H et al Determinants of good adherence to handhygiene among healthcare workers who have extensive exposure to handhygiene campaigns Infect Control Hosp Epidemiol 2007281267ndash74httpsdoiorg101086521663

8 Gurses AP Seidl KL Vaidya V et al Systems ambiguity and guidelinecompliance a qualitative study of how intensive care units follow evidence-based guidelines to reduce healthcare-associated infections Qual Saf HealthCare 200817351ndash9 httpsdoiorg101136qshc2006021709

9 Grundgeiger T Sanderson PM Orihuela CB et al Prospective memoryin the ICU the effect of visual cues on task execution in arepresentative simulation Ergonomics 201356579ndash89 httpsdoiorg101080001401392013765604

Fig 9 The final signage solution for combined precautions Legend These signs have been translated from German to English for publication

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 12 of 13

concerns with this idea during the prototyping phasethese participants instead employed masks suspended inthe doorway through which healthcare providers mustwalk thereby automatically donning a mask upon roomentry Such solutions must be assessed to ensure theirsafety prior to introduction Employing such forcingfunctions would address issues of forgetting which par-ticipants confirmed is one of the main reasons for pro-cedural noncompliance

Not ldquobreaking the flow of workrdquoSeveral participants expressed that a major barrier tocompliance with isolation precautions is the time neces-sary to find out which precautions are applicable and lo-cate and don the materials necessary for complianceThis was expressed in the problem statement ldquohowmight we save time while respecting isolation precau-tionsrdquo Participants proposed multiple solutions Indicat-ing on the signage both the type of isolation as well asthe necessary precautions eliminates the cognitive loadrequired for those entering the room and saves time ne-cessary to identify the relevant guidelines and materialsFigure 6 demonstrates both the ideation and prototypingof one such solution which sends a strong visual cue in-dicating the type of protective equipment that should beemployed

Placement of visual cuesAnother theme identified during the workshops was thatthe current provision of visual cues (only at the entranceto the patient room) is inadequate When prompted

about where visual cues should be located the majorityof participants indicated that some cues should also belocated inside the patient room The most commonlyproposed locations for visual cues included at the en-trance to the patient room at the foot of the patientbed and next to patient charts

Prototyping and evaluationSymbol development and judgement testDuring design thinking workshops participants gener-ated ideas and sketches about how to portray the threemain isolation categories (contact droplet and airborne)as symbols (Additional file 1) Variants of each isolationsymbol [contact isolation (n = 4) droplet isolation (n =5) and airborne isolation (n = 6)] were then designedemploying the same themes that emerged from the par-ticipants themselves in order to be consistent with usermental models and thus increase comprehension Re-spondentsrsquo judgements of how many of their colleagueswould understand the symbols ranged from 17 to 78(Additional file 2) Of note the variants that picturedtwo whole human figures performed better in judgementtesting than those without the human figure or part ofthe human body (eg only hands) The highest rated var-iants of each symbol were retained and further examinedthrough a comprehensibility test

Symbol comprehensibility testDetailed results of the comprehensibility testing can befound in Additional file 2 Whereas the symbols for con-tact and droplet isolation were correctly understood by a

Fig 4 Existing signage for housekeeping (left) with ldquopatchrdquo to clarify ambiguous mask indication (right) Legend This ldquopatchrdquo introduced byhousekeeping personnel suggests that the existing signage provided ambiguous instructions and that they preferred a more simple instructionto don a mask The patch indicated with an arrow reads ldquowith maskrdquo instead of ldquosurgical mask if necessaryrdquo The existing signage (left) wastranslated from German to English for publication

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 6 of 13

Table 1 Established personas

Persona Description User requirements

Julia Internal Medicine NurseAge 25

bull Julia began working in the internal medicine ward atthe USZ directly after finishing her nursing degreeHaving freshly finished her schooling she looks up tothe more experienced nurses

bull She is especially vigilant in her infection controlpractices including isolation precautions as this was amajor focus of her training

bull When she is not sure about which isolation precautionsshe should use for a patient she (erroneously)references the sign on the housekeeping cart

bull Signage should offer multiple levels of information forfrequent versus rare users For example recognition ofthe standardised signage colour may be enough forfrequent users to recall the necessary precautionswhereas rare users need to be reminded of the specificprecautions

bull Target audience must be clearly distinguishable

Sarah Nursing assistantAge 48

bull Sarah has worked in several wards of the USZ One ofthe highlights of her job is that it allows her to have aclose relationship with patients

bull She has a hard time bringing up isolation with herpatients because she sympathises with the emotionaleffects this may have For the same reason shesometimes neglects to respect hygiene measures suchas hand hygiene and wearing gowns as she feels thisputs a separation between herself and the patient

bull Signage should aim to establish social norms increaseacceptability of performing infection preventionmeasures

Paul Emergency WardPhysician Age 42

bull During medical school in Germany Paul chose tospecialise in emergency medicine because Dr Housewas his favourite TV drama and he enjoys the challengeand rush to resolve critical situations

bull Paulrsquos career took off quickly after he successfullypublished a highly cited paper in New England Journalof Medicine and he became known as an expert influid management in poly-trauma patients

bull In the rush of acute care situations infection controlmeasures sometimes take a back seat but no one daresto correct this senior physician

bull Signage must quickly communicate essentialinformation and must not require extra time

bull Barriers to performing isolation precautions (egmissing materials) should be removed

bull Signage should aim to support psychological safety(eg speaking up)

Omar Porter Age 55 bull Prior to moving to Switzerland with his family five yearsago Omar was an elementary school teacher in TunisiaHe came to Switzerland with no prior Germanknowledge but was able to begin working in thehospital while simultaneously taking German classes

bull When he began working he relied on clear photos andsymbols to help him interpret written protocols

bull Signage must be able to communicate effectively withstaff for whom German is not a native language forexample with self-explanatory images

Teresa Housekeeping staffAge 46

bull Teresa is specially assigned to work in the emergencyward where they have specific cleaning andmaintenance procedures from the rest of the hospitalHer native language is Portuguese but her outgoingpersonality helped her to quickly learn German throughchatting with her colleagues when she began working

bull Signage content may need to be adapted for specificsettings

bull Signage must be able to communicate effectively withstaff for whom German is not a native language forexample with self-explanatory images

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 7 of 13

majority of participants the symbols for airborne isola-tion were sometimes incorrectly interpreted as meaningdroplet isolation The three variants with the highestcomprehensibility and least conflicting interpretationswere retained for use in further signage prototypes(Fig 7)

Iterative prototyping and evaluationThe process of iterative prototyping and evaluation of iso-lation signage occurred in parallel to the testing of sym-bols During this process several prototypes emerged withvarying levels of sophistication In the earliest stages ideaswere expressed on paper in the form of sketches Thosesketches with the most positive feedback from the targetpopulation were then transformed into more sophisticatedprototypes As prototypes were continually evaluatedthrough informal discussions with frontline HCPs theirfeedback provided insights that led to further refining ofconsecutive prototypes Experts in infection preventionand control were regularly consulted to ensure accuracyof the signage content This iterative design process asdocumented in Additional file 3 continued until satur-ation was achieved (ie until no new feedback was given)

Final signage solutionThe final solutions that resulted from the iterative proto-typing and evaluation process were shared with agraphic designer to produce the final signage system forthe three main isolation categories (Fig 8) as well as twosigns for combined precautions (Fig 9) This solutionfeatures a caution tape graphic and salient colours todraw attention to those entering the room that specialprecautions must be taken The isolation categories arecommunicated dually through the colour which is stan-dardised throughout all isolation precaution documentsand the prominent symbol portraying the transmissionpathway The specific precautions are portrayed in theorder in which they must be performed removing

method ambiguity The use of text is limited and thesignage relies largely on user-friendly graphics to sup-port comprehension regardless of language proficiencyThe signage is available for download on the intranetand can be printed with one sign per A4 sheet of paperBeyond the scope of the physical signage hospital guide-lines have also been introduced that limit the amountand type of information that can be posted on patientdoors which increases the saliency of remaining signageIn collaboration with the infection prevention depart-ment the housekeeping department has also revisedtheir isolation precaution guidelines and brochures toeliminate confusion with signage intended for HCPsThe signs were implemented by e-mailing heads of

wards to inform them of the new signage announce-ment and posting of the new signs on the intranet ser-ver and physically distributing printed signs to eachhospital ward according to number of beds Additionalcopies were made available for order Physical copiesand links to the previous signage were removed

DiscussionThis paper describes the successful application of a user-centred participatory design process to develop a sign-age system for communicating isolation precautionsThe resulting signage system aims to serve as a visualcue for HCPs remove ambiguity and elicit safe infectionprevention behaviours to ultimately prevent the trans-mission of infectious agentsOur analysis of existing isolation signage revealed that

ambiguity was indeed a major factor responsible fornon-compliance with transmission-based precautions inour hospital This is consistent with the findings ofGurses et al who propose systems ambiguity as aframework to explain procedural non-compliance inhealthcare [8] Ambiguity in our institution was identi-fied mainly in the form of task ambiguity (not knowingwhich guidelines are applicable for which patients) and

Table 1 Established personas (Continued)

Persona Description User requirements

at the USZ even picking up a Swiss German accentbull She has been working in the emergency ward for 12years now and although she has no medical trainingshe is excellent at what she does

Legend Personas fictional characters based on input from real users were established to understand the needs and goals of the individuals who will interactwith the signage system and to guide the subsequent design process

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 8 of 13

method ambiguity (not knowing how or in which orderto complete a particular guideline) This was due to thelack of indication about which category of isolation a pa-tient was under or which preventative measures wereapplicable To specifically address barriers related to taskand method ambiguity the new signage was designedwith the intent of bringing isolation guidelines directlyto the frontline where their use is indicated also re-ferred to as placing ldquoknowledge in the worldrdquo [23 24]The symbols and colour-scheme developed to portray

isolation categories (contact droplet and airborne) weredeemed to be an important part of the overall signagewith the intention that these may become standardisedthroughout the institution and thus increase recognitionand compliance The comprehensibility evaluation ofthese symbols revealed that the airborne and droplet iso-lation symbols were the most often confounded This isnot surprising due to the similar means by which bothairborne particles and droplets can be propelled into theenvironment through coughing and sneezing In orderto further distinguish these symbols they have beenassociated in the new signage with standardised colourscheme where airborne is blue droplet is green andcontact is orange The standardisation of these colourschemes is intended to further aid in the distinction ofdifferent isolation categories and make them quicklyrecognisable once they have been learned through re-peated exposure

Table 2 Identified design requirements

Functional requirements (what the system should do)

Informationdissemination

bull Draw the attention of anyone entering the room thatspecial precautions must be taken

bull Inform any person entering the patient room whatisolation status that patient has

bull Inform any person entering the patient room aboutthe isolation precautions they must employ accordingto the patientrsquos isolation status

Inform healthcare personnel about requiredpersonal protective equipment

Inform cleaning staff about required protectiveequipment adapted disinfectants and prioritisedcleaning measures

Inform visitors about required personal protectiveequipment or instruct them to see a staff member

bull Inform any person entering the room about the orderin which precautions (eg donning and doffingpersonal protective equipment hand hygiene) shouldbe performed

bull Inform anyone transporting the patient about thetransmission-based precautions that shouldbe respected

bull In addition to the three main categories oftransmission-based precautions (contact droplet andairborne) signage should also be designed tocommunicate combined or ldquolightrdquo isolationprecautions specific to the USZ

USZ guidelines bull Be consistent with USZ guidelines for isolationprecautions The three main isolationcategories include

Contact isolation don gown Droplet isolation don surgical mask Airborne isolation don FFP2 mask

bull Communicate combined isolation precautions Contact + Droplet isolation don gown andsurgical mask

Contact + Airborne isolation don gown andFFP2 mask

Non-functional requirements(constraints on the system and its development)

Maintenancerestraints

bull Must be easy to hang and remove on an as-need basisbull If printed on paper must either be laminate so that itmay be cleaned and reused or single use

Accessibilityandconfidentialityrequirements

bull Should include graphics and symbols to accommodatenon-native German speaking personnel

bull Signage should avoid potential patient stigmatisationand should not disclose any confidentialpatient information

bull Signage must be accessible to individuals with colourvision deficiency for example by avoiding problematiccolour combinations and employing both colours andsymbols to convey messages over multiple channels

Physicalenvironmentrequirements

bull Signage must be noticeable relative to other signs inthe healthcare setting(appropriate single-to-noise ratio)

bull Some indication of the patientrsquos isolation statusshould travel with the patient at all times so that theappropriate transmission-based precautions can becommunicated at all times (eg when the patient isoutside of the room where the sign is posted) ndash thiscould be attached to the patient herself or to thepatientrsquos bed

bull Signage for housekeeping personnel should be of aportable size (A4 or smaller) so that it can fit on thecleaning trolleys

Organisational bull The signage should be able to quickly communicate

Table 2 Identified design requirements (Continued)

environmentrequirements

the required actions so that healthcare providers donot need to slow down (lsquobreak the rhythmrsquo) tointerpret them

bull If sign will be paper-based it should be easilyaccessible to staff on the ward when an isolatedpatient arrives (eg printed copies from intranet)or purchasable

bull Any posted signs must be consistent with theCorporate Design Guidelines

bull Information communicated through signage must beconsistent with evidence based-guidelines such as theCDC 2007 guidance as well as institutional infectioncontrol guidelines

Technicalenvironmentrequirements

bull Colour printer must be available if units are to printtheir own copies of paper-based signage

bull Intranet connection must be available if units are todownload the signs

bull Staff must be able to post the signage either by usingan adhesive material or the signs may be printeddirectly onto an adhesive sheet

bull Handling of signage material should be cost-effectiveand practical in every-day use

bull It should be possible to update the signage systemeasily in case new hospital rulesguidelinesare introduced

Legend Design requirements identified during interviews and observationsserved as a guide to ensure that subsequent designs met user needs whilesatisfying functional and non-functional requirements USZ University HospitalZurich CDC Centers for Disease Control

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 9 of 13

It is commonly accepted that ldquoconcept-relatedrdquo sym-bols which are abstract representations of the referentor subject they represent require more training beforethey can be understood by viewers [25] However by de-signing symbols for isolation precaution signage suchthat they are consistent with mental models this projectaimed to achieve a design that requires minimal trainingand that may also be intuitively understood Interest-ingly comprehensibility testing revealed that symbolsshowing the whole human figure were rated higher thanthose without the human figure or with an abstract partof the human body (eg only hands) This finding is con-sistent with results of the Hablamos Juntos Report who

evaluated the usability of several symbols for use in way-finding signage in hospital settings and found that symbolswith the whole human body were best understood [12]In addition to comprehensibility benefits including

the human figure particularly human eyes may be im-portant as it relates to emotional design Multiple studieshave examined the effect of images of human eyes oncooperative behaviour such as an ldquohonour systemrdquomethod of payment to an honesty box to pay for drinksin a coffee room [26] Such studies have found that thepresence of eye images act as a subtle cue and thatpeople paid as much as three times more often for theirdrinks when human eyes were displayed as opposed to

Fig 5 Workshop example of ldquoforcing functionrdquo during ideation (left) and prototyping (right) phases Legend This extract from a design thinkingworkshop shows one participantrsquos proposal to use a ldquoforcing functionrdquo to ensure that hands are disinfected prior to entry The middle shows adoor handle that only opens when alcohol is detected The right shows a prototype featuring the forcing function of a mask suspended in thedoorway through which clinicians must walk and thereby don masks upon room entry

Fig 6 Idea (left) and Prototype (right) of signage from design thinking workshop Legend This prototype developed during a design thinkingworkshop sends a strong visual cue about the necessary precautions The sign reads ldquoWarning before entering helliprdquo

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 10 of 13

when a neutral control image was displayed [27] Studiesin infection prevention settings however have hadmixed success in reproducing this effect [28ndash30] Furtherstudies on this topic are warranted to better understandhow signage may be employed to prime cooperative be-haviour and thus improve guideline adherenceThe field of infection prevention and patient safety is

rife with opportunities to actively include HCPs in user-centred design processes to improve healthcare environ-ments and practises The participatory design approachwas well suited for this inquiry as it allowed us to activelyinvolve stakeholders with essential insights thereby estab-lishing ownership and increasing chances of acceptanceand sustainability of the new signage The benefits of col-laborating with frontline HCPs extend beyond the scopeof the resulting design to also improve the image of theInfection Control department as a resource and to nurturethe possibility of further collaboration Recent reviews onthe use of participatory approaches such as experience-based co-design or co-production in which patients andhealthcare staff are engaged to improve health servicesreport outcomes related to the value of patient and staffinvolvement the quantity and quality of ideas and sugges-tions to modify practices and tangible changes in servicedelivery and user experience [31 32]Some limitations of this study should be considered

During this study we were faced with the challenge of

changing institutional guidelines for isolation precau-tions This prevented a quantitative analysis of change inpractice and presented a challenge during the evaluationwith frontline staff who were not yet familiar with thenew guidelines and thus had a tendency to focus on thediscrepancies between the ldquonewrdquo vs the current guide-lines rather than signage design The latter was ad-dressed through discussion with participants about thepossibility of new evidence-based practices and also bypresenting frontline users with prototypes that were con-sistent with their existing mental models ie consistentwith current guidelines Also the introduction of suchsignage is intended to serve as a visual cue and to re-move ambiguity regarding which precautions should beused and when The introduction of such signage how-ever does not entirely remove other known barriers tocompliance with isolation precautions such as ldquolack oftimerdquo [33] or ldquoavailability of protective clothingrdquo [5] It isthus imperative that the introduction of such signagetakes place within the context of a systems approach en-suring for example that the necessary time and materialresources are also available in order to mitigate thesebarriers

ConclusionsIn conclusion this study resulted in a user-centred sign-age design solution and set of comprehensible symbols

Fig 7 Symbols for contact (left) droplet (middle) and airborne (right) isolation Legend The variants of each symbol with the highest judgementand comprehensibility ratings were retained for use in further signage development phases

Fig 8 The final signage solution for contact (left) droplet (middle) and airborne (right) isolation Legend The final solution to be printed withone sign per A4 sheet incorporates several features to satisfy the identified design requirements These signs have been translated from Germanto English for publication

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 11 of 13

to remove ambiguity and to make compliance withevidence-based guidelines easy and intuitive for HCPsand visitors to the USZ The introduction of signageparticularly for infection control offers a promising op-portunity to make guidelines available directly at thefrontline where their use is indicated thereby reducingthe need for training and standard operating proceduresThis article further describes the application of a user-centred participatory design process which has great po-tential for application in the field of hospital infectioncontrol to design solutions that make performing infec-tion prevention behaviours easy and intuitive

Supplementary informationSupplementary information accompanies this paper at httpsdoiorg101186s13756-019-0629-9

Additional file 1 Pictorial portrayal of isolation categories

Additional file 2 Results of Judgement and Comprehension testing

Additional file 3 Iterations of Isolation Signage System

AbbreviationsCDC Centers for Disease Control HAI Healthcare-associated infectionsHCP Healthcare provider ID Infectious diseases IPC Infection preventionand control USZ University Hospital Zurich

AcknowledgementsWe would like to warmly acknowledge all study participants We would alsolike to acknowledge Andreacute Rothfuchs of Studio Sirup who provided graphicdesign services for the final signage solution

Authorsrsquo contributionsLC and HS conceived and designed the study LC conducted data collectionanalysis and iterative signage design and evaluation MS MM and AWprovided iterative feedback to inform the final signage solution LC draftedthe manuscript and all authors provided detailed feedback and approvedthe final manuscript

FundingThis work was partially funded by the Swiss National Science Foundation(32003B_149474) and by the University Hospital of Zurich Department ofQuality Management and Patient Safety

Availability of data and materialsThe datasets used andor analysed during the current study are availablefrom the corresponding author on reasonable request

Ethics approval and consent to participateThe Zurich Cantonal Ethics Committee waived the need for formal ethicsreview of this project (KEK-StV-Nr 4114) Participation in all study activitieswas voluntary and participants were free to withdraw at any time Allinterview and workshop participants provided written informed consentprior to participation

Consent for publicationNot applicable

Competing interestsThe authors declare that they have no competing interests

Author details1Division of Infectious Diseases and Hospital Epidemiology UniversityHospital Zurich and University of Zurich Raemistrasse 100 HAL14 8091Zurich Switzerland 2Department of Management Technology andEconomics ETH Zurich Zurich Switzerland

Received 9 August 2019 Accepted 16 October 2019

References1 World Health Organization (WHO) Report on the burden of endemic health

care-associated infection wordwide Geneva World Health Organization2011

2 Siegel JD Rhinehard E Jackson M et al 2007 guideline for isolationprecautions preventing transmission of infectious agents in healthcaresettings 2007

3 Larson E Kretzer EK Compliance with handwashing and barrier precautionsJ Hosp Infect 199530(Suppl)88ndash106

4 Weber D Sickbert-Bennett EE Brown VM et al Compliance withisolation precautions at a university hospital Infect Control HospEpidemiol 200728358ndash61

5 Gammon J Morgan-Samuel H Gould D A review of the evidence forsuboptimal compliance of healthcare practitioners to standarduniversalinfection control precautions J Clin Nurs 200817157ndash67 httpsdoiorg101111j1365-2702200601852x

6 Sax H Perneger T Hugonnet S et al Knowledge of standard and isolationprecautions in a large teaching hospital Infect Control Hosp Epidemiol200526298ndash304 httpsdoiorg101086502543

7 Sax H Uckay I Richet H et al Determinants of good adherence to handhygiene among healthcare workers who have extensive exposure to handhygiene campaigns Infect Control Hosp Epidemiol 2007281267ndash74httpsdoiorg101086521663

8 Gurses AP Seidl KL Vaidya V et al Systems ambiguity and guidelinecompliance a qualitative study of how intensive care units follow evidence-based guidelines to reduce healthcare-associated infections Qual Saf HealthCare 200817351ndash9 httpsdoiorg101136qshc2006021709

9 Grundgeiger T Sanderson PM Orihuela CB et al Prospective memoryin the ICU the effect of visual cues on task execution in arepresentative simulation Ergonomics 201356579ndash89 httpsdoiorg101080001401392013765604

Fig 9 The final signage solution for combined precautions Legend These signs have been translated from German to English for publication

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 12 of 13

Table 1 Established personas

Persona Description User requirements

Julia Internal Medicine NurseAge 25

bull Julia began working in the internal medicine ward atthe USZ directly after finishing her nursing degreeHaving freshly finished her schooling she looks up tothe more experienced nurses

bull She is especially vigilant in her infection controlpractices including isolation precautions as this was amajor focus of her training

bull When she is not sure about which isolation precautionsshe should use for a patient she (erroneously)references the sign on the housekeeping cart

bull Signage should offer multiple levels of information forfrequent versus rare users For example recognition ofthe standardised signage colour may be enough forfrequent users to recall the necessary precautionswhereas rare users need to be reminded of the specificprecautions

bull Target audience must be clearly distinguishable

Sarah Nursing assistantAge 48

bull Sarah has worked in several wards of the USZ One ofthe highlights of her job is that it allows her to have aclose relationship with patients

bull She has a hard time bringing up isolation with herpatients because she sympathises with the emotionaleffects this may have For the same reason shesometimes neglects to respect hygiene measures suchas hand hygiene and wearing gowns as she feels thisputs a separation between herself and the patient

bull Signage should aim to establish social norms increaseacceptability of performing infection preventionmeasures

Paul Emergency WardPhysician Age 42

bull During medical school in Germany Paul chose tospecialise in emergency medicine because Dr Housewas his favourite TV drama and he enjoys the challengeand rush to resolve critical situations

bull Paulrsquos career took off quickly after he successfullypublished a highly cited paper in New England Journalof Medicine and he became known as an expert influid management in poly-trauma patients

bull In the rush of acute care situations infection controlmeasures sometimes take a back seat but no one daresto correct this senior physician

bull Signage must quickly communicate essentialinformation and must not require extra time

bull Barriers to performing isolation precautions (egmissing materials) should be removed

bull Signage should aim to support psychological safety(eg speaking up)

Omar Porter Age 55 bull Prior to moving to Switzerland with his family five yearsago Omar was an elementary school teacher in TunisiaHe came to Switzerland with no prior Germanknowledge but was able to begin working in thehospital while simultaneously taking German classes

bull When he began working he relied on clear photos andsymbols to help him interpret written protocols

bull Signage must be able to communicate effectively withstaff for whom German is not a native language forexample with self-explanatory images

Teresa Housekeeping staffAge 46

bull Teresa is specially assigned to work in the emergencyward where they have specific cleaning andmaintenance procedures from the rest of the hospitalHer native language is Portuguese but her outgoingpersonality helped her to quickly learn German throughchatting with her colleagues when she began working

bull Signage content may need to be adapted for specificsettings

bull Signage must be able to communicate effectively withstaff for whom German is not a native language forexample with self-explanatory images

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 7 of 13

majority of participants the symbols for airborne isola-tion were sometimes incorrectly interpreted as meaningdroplet isolation The three variants with the highestcomprehensibility and least conflicting interpretationswere retained for use in further signage prototypes(Fig 7)

Iterative prototyping and evaluationThe process of iterative prototyping and evaluation of iso-lation signage occurred in parallel to the testing of sym-bols During this process several prototypes emerged withvarying levels of sophistication In the earliest stages ideaswere expressed on paper in the form of sketches Thosesketches with the most positive feedback from the targetpopulation were then transformed into more sophisticatedprototypes As prototypes were continually evaluatedthrough informal discussions with frontline HCPs theirfeedback provided insights that led to further refining ofconsecutive prototypes Experts in infection preventionand control were regularly consulted to ensure accuracyof the signage content This iterative design process asdocumented in Additional file 3 continued until satur-ation was achieved (ie until no new feedback was given)

Final signage solutionThe final solutions that resulted from the iterative proto-typing and evaluation process were shared with agraphic designer to produce the final signage system forthe three main isolation categories (Fig 8) as well as twosigns for combined precautions (Fig 9) This solutionfeatures a caution tape graphic and salient colours todraw attention to those entering the room that specialprecautions must be taken The isolation categories arecommunicated dually through the colour which is stan-dardised throughout all isolation precaution documentsand the prominent symbol portraying the transmissionpathway The specific precautions are portrayed in theorder in which they must be performed removing

method ambiguity The use of text is limited and thesignage relies largely on user-friendly graphics to sup-port comprehension regardless of language proficiencyThe signage is available for download on the intranetand can be printed with one sign per A4 sheet of paperBeyond the scope of the physical signage hospital guide-lines have also been introduced that limit the amountand type of information that can be posted on patientdoors which increases the saliency of remaining signageIn collaboration with the infection prevention depart-ment the housekeeping department has also revisedtheir isolation precaution guidelines and brochures toeliminate confusion with signage intended for HCPsThe signs were implemented by e-mailing heads of

wards to inform them of the new signage announce-ment and posting of the new signs on the intranet ser-ver and physically distributing printed signs to eachhospital ward according to number of beds Additionalcopies were made available for order Physical copiesand links to the previous signage were removed

DiscussionThis paper describes the successful application of a user-centred participatory design process to develop a sign-age system for communicating isolation precautionsThe resulting signage system aims to serve as a visualcue for HCPs remove ambiguity and elicit safe infectionprevention behaviours to ultimately prevent the trans-mission of infectious agentsOur analysis of existing isolation signage revealed that

ambiguity was indeed a major factor responsible fornon-compliance with transmission-based precautions inour hospital This is consistent with the findings ofGurses et al who propose systems ambiguity as aframework to explain procedural non-compliance inhealthcare [8] Ambiguity in our institution was identi-fied mainly in the form of task ambiguity (not knowingwhich guidelines are applicable for which patients) and

Table 1 Established personas (Continued)

Persona Description User requirements

at the USZ even picking up a Swiss German accentbull She has been working in the emergency ward for 12years now and although she has no medical trainingshe is excellent at what she does

Legend Personas fictional characters based on input from real users were established to understand the needs and goals of the individuals who will interactwith the signage system and to guide the subsequent design process

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 8 of 13

method ambiguity (not knowing how or in which orderto complete a particular guideline) This was due to thelack of indication about which category of isolation a pa-tient was under or which preventative measures wereapplicable To specifically address barriers related to taskand method ambiguity the new signage was designedwith the intent of bringing isolation guidelines directlyto the frontline where their use is indicated also re-ferred to as placing ldquoknowledge in the worldrdquo [23 24]The symbols and colour-scheme developed to portray

isolation categories (contact droplet and airborne) weredeemed to be an important part of the overall signagewith the intention that these may become standardisedthroughout the institution and thus increase recognitionand compliance The comprehensibility evaluation ofthese symbols revealed that the airborne and droplet iso-lation symbols were the most often confounded This isnot surprising due to the similar means by which bothairborne particles and droplets can be propelled into theenvironment through coughing and sneezing In orderto further distinguish these symbols they have beenassociated in the new signage with standardised colourscheme where airborne is blue droplet is green andcontact is orange The standardisation of these colourschemes is intended to further aid in the distinction ofdifferent isolation categories and make them quicklyrecognisable once they have been learned through re-peated exposure

Table 2 Identified design requirements

Functional requirements (what the system should do)

Informationdissemination

bull Draw the attention of anyone entering the room thatspecial precautions must be taken

bull Inform any person entering the patient room whatisolation status that patient has

bull Inform any person entering the patient room aboutthe isolation precautions they must employ accordingto the patientrsquos isolation status

Inform healthcare personnel about requiredpersonal protective equipment

Inform cleaning staff about required protectiveequipment adapted disinfectants and prioritisedcleaning measures

Inform visitors about required personal protectiveequipment or instruct them to see a staff member

bull Inform any person entering the room about the orderin which precautions (eg donning and doffingpersonal protective equipment hand hygiene) shouldbe performed

bull Inform anyone transporting the patient about thetransmission-based precautions that shouldbe respected

bull In addition to the three main categories oftransmission-based precautions (contact droplet andairborne) signage should also be designed tocommunicate combined or ldquolightrdquo isolationprecautions specific to the USZ

USZ guidelines bull Be consistent with USZ guidelines for isolationprecautions The three main isolationcategories include

Contact isolation don gown Droplet isolation don surgical mask Airborne isolation don FFP2 mask

bull Communicate combined isolation precautions Contact + Droplet isolation don gown andsurgical mask

Contact + Airborne isolation don gown andFFP2 mask

Non-functional requirements(constraints on the system and its development)

Maintenancerestraints

bull Must be easy to hang and remove on an as-need basisbull If printed on paper must either be laminate so that itmay be cleaned and reused or single use

Accessibilityandconfidentialityrequirements

bull Should include graphics and symbols to accommodatenon-native German speaking personnel

bull Signage should avoid potential patient stigmatisationand should not disclose any confidentialpatient information

bull Signage must be accessible to individuals with colourvision deficiency for example by avoiding problematiccolour combinations and employing both colours andsymbols to convey messages over multiple channels

Physicalenvironmentrequirements

bull Signage must be noticeable relative to other signs inthe healthcare setting(appropriate single-to-noise ratio)

bull Some indication of the patientrsquos isolation statusshould travel with the patient at all times so that theappropriate transmission-based precautions can becommunicated at all times (eg when the patient isoutside of the room where the sign is posted) ndash thiscould be attached to the patient herself or to thepatientrsquos bed

bull Signage for housekeeping personnel should be of aportable size (A4 or smaller) so that it can fit on thecleaning trolleys

Organisational bull The signage should be able to quickly communicate

Table 2 Identified design requirements (Continued)

environmentrequirements

the required actions so that healthcare providers donot need to slow down (lsquobreak the rhythmrsquo) tointerpret them

bull If sign will be paper-based it should be easilyaccessible to staff on the ward when an isolatedpatient arrives (eg printed copies from intranet)or purchasable

bull Any posted signs must be consistent with theCorporate Design Guidelines

bull Information communicated through signage must beconsistent with evidence based-guidelines such as theCDC 2007 guidance as well as institutional infectioncontrol guidelines

Technicalenvironmentrequirements

bull Colour printer must be available if units are to printtheir own copies of paper-based signage

bull Intranet connection must be available if units are todownload the signs

bull Staff must be able to post the signage either by usingan adhesive material or the signs may be printeddirectly onto an adhesive sheet

bull Handling of signage material should be cost-effectiveand practical in every-day use

bull It should be possible to update the signage systemeasily in case new hospital rulesguidelinesare introduced

Legend Design requirements identified during interviews and observationsserved as a guide to ensure that subsequent designs met user needs whilesatisfying functional and non-functional requirements USZ University HospitalZurich CDC Centers for Disease Control

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 9 of 13

It is commonly accepted that ldquoconcept-relatedrdquo sym-bols which are abstract representations of the referentor subject they represent require more training beforethey can be understood by viewers [25] However by de-signing symbols for isolation precaution signage suchthat they are consistent with mental models this projectaimed to achieve a design that requires minimal trainingand that may also be intuitively understood Interest-ingly comprehensibility testing revealed that symbolsshowing the whole human figure were rated higher thanthose without the human figure or with an abstract partof the human body (eg only hands) This finding is con-sistent with results of the Hablamos Juntos Report who

evaluated the usability of several symbols for use in way-finding signage in hospital settings and found that symbolswith the whole human body were best understood [12]In addition to comprehensibility benefits including

the human figure particularly human eyes may be im-portant as it relates to emotional design Multiple studieshave examined the effect of images of human eyes oncooperative behaviour such as an ldquohonour systemrdquomethod of payment to an honesty box to pay for drinksin a coffee room [26] Such studies have found that thepresence of eye images act as a subtle cue and thatpeople paid as much as three times more often for theirdrinks when human eyes were displayed as opposed to

Fig 5 Workshop example of ldquoforcing functionrdquo during ideation (left) and prototyping (right) phases Legend This extract from a design thinkingworkshop shows one participantrsquos proposal to use a ldquoforcing functionrdquo to ensure that hands are disinfected prior to entry The middle shows adoor handle that only opens when alcohol is detected The right shows a prototype featuring the forcing function of a mask suspended in thedoorway through which clinicians must walk and thereby don masks upon room entry

Fig 6 Idea (left) and Prototype (right) of signage from design thinking workshop Legend This prototype developed during a design thinkingworkshop sends a strong visual cue about the necessary precautions The sign reads ldquoWarning before entering helliprdquo

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 10 of 13

when a neutral control image was displayed [27] Studiesin infection prevention settings however have hadmixed success in reproducing this effect [28ndash30] Furtherstudies on this topic are warranted to better understandhow signage may be employed to prime cooperative be-haviour and thus improve guideline adherenceThe field of infection prevention and patient safety is

rife with opportunities to actively include HCPs in user-centred design processes to improve healthcare environ-ments and practises The participatory design approachwas well suited for this inquiry as it allowed us to activelyinvolve stakeholders with essential insights thereby estab-lishing ownership and increasing chances of acceptanceand sustainability of the new signage The benefits of col-laborating with frontline HCPs extend beyond the scopeof the resulting design to also improve the image of theInfection Control department as a resource and to nurturethe possibility of further collaboration Recent reviews onthe use of participatory approaches such as experience-based co-design or co-production in which patients andhealthcare staff are engaged to improve health servicesreport outcomes related to the value of patient and staffinvolvement the quantity and quality of ideas and sugges-tions to modify practices and tangible changes in servicedelivery and user experience [31 32]Some limitations of this study should be considered

During this study we were faced with the challenge of

changing institutional guidelines for isolation precau-tions This prevented a quantitative analysis of change inpractice and presented a challenge during the evaluationwith frontline staff who were not yet familiar with thenew guidelines and thus had a tendency to focus on thediscrepancies between the ldquonewrdquo vs the current guide-lines rather than signage design The latter was ad-dressed through discussion with participants about thepossibility of new evidence-based practices and also bypresenting frontline users with prototypes that were con-sistent with their existing mental models ie consistentwith current guidelines Also the introduction of suchsignage is intended to serve as a visual cue and to re-move ambiguity regarding which precautions should beused and when The introduction of such signage how-ever does not entirely remove other known barriers tocompliance with isolation precautions such as ldquolack oftimerdquo [33] or ldquoavailability of protective clothingrdquo [5] It isthus imperative that the introduction of such signagetakes place within the context of a systems approach en-suring for example that the necessary time and materialresources are also available in order to mitigate thesebarriers

ConclusionsIn conclusion this study resulted in a user-centred sign-age design solution and set of comprehensible symbols

Fig 7 Symbols for contact (left) droplet (middle) and airborne (right) isolation Legend The variants of each symbol with the highest judgementand comprehensibility ratings were retained for use in further signage development phases

Fig 8 The final signage solution for contact (left) droplet (middle) and airborne (right) isolation Legend The final solution to be printed withone sign per A4 sheet incorporates several features to satisfy the identified design requirements These signs have been translated from Germanto English for publication

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 11 of 13

to remove ambiguity and to make compliance withevidence-based guidelines easy and intuitive for HCPsand visitors to the USZ The introduction of signageparticularly for infection control offers a promising op-portunity to make guidelines available directly at thefrontline where their use is indicated thereby reducingthe need for training and standard operating proceduresThis article further describes the application of a user-centred participatory design process which has great po-tential for application in the field of hospital infectioncontrol to design solutions that make performing infec-tion prevention behaviours easy and intuitive

Supplementary informationSupplementary information accompanies this paper at httpsdoiorg101186s13756-019-0629-9

Additional file 1 Pictorial portrayal of isolation categories

Additional file 2 Results of Judgement and Comprehension testing

Additional file 3 Iterations of Isolation Signage System

AbbreviationsCDC Centers for Disease Control HAI Healthcare-associated infectionsHCP Healthcare provider ID Infectious diseases IPC Infection preventionand control USZ University Hospital Zurich

AcknowledgementsWe would like to warmly acknowledge all study participants We would alsolike to acknowledge Andreacute Rothfuchs of Studio Sirup who provided graphicdesign services for the final signage solution

Authorsrsquo contributionsLC and HS conceived and designed the study LC conducted data collectionanalysis and iterative signage design and evaluation MS MM and AWprovided iterative feedback to inform the final signage solution LC draftedthe manuscript and all authors provided detailed feedback and approvedthe final manuscript

FundingThis work was partially funded by the Swiss National Science Foundation(32003B_149474) and by the University Hospital of Zurich Department ofQuality Management and Patient Safety

Availability of data and materialsThe datasets used andor analysed during the current study are availablefrom the corresponding author on reasonable request

Ethics approval and consent to participateThe Zurich Cantonal Ethics Committee waived the need for formal ethicsreview of this project (KEK-StV-Nr 4114) Participation in all study activitieswas voluntary and participants were free to withdraw at any time Allinterview and workshop participants provided written informed consentprior to participation

Consent for publicationNot applicable

Competing interestsThe authors declare that they have no competing interests

Author details1Division of Infectious Diseases and Hospital Epidemiology UniversityHospital Zurich and University of Zurich Raemistrasse 100 HAL14 8091Zurich Switzerland 2Department of Management Technology andEconomics ETH Zurich Zurich Switzerland

Received 9 August 2019 Accepted 16 October 2019

References1 World Health Organization (WHO) Report on the burden of endemic health

care-associated infection wordwide Geneva World Health Organization2011

2 Siegel JD Rhinehard E Jackson M et al 2007 guideline for isolationprecautions preventing transmission of infectious agents in healthcaresettings 2007

3 Larson E Kretzer EK Compliance with handwashing and barrier precautionsJ Hosp Infect 199530(Suppl)88ndash106

4 Weber D Sickbert-Bennett EE Brown VM et al Compliance withisolation precautions at a university hospital Infect Control HospEpidemiol 200728358ndash61

5 Gammon J Morgan-Samuel H Gould D A review of the evidence forsuboptimal compliance of healthcare practitioners to standarduniversalinfection control precautions J Clin Nurs 200817157ndash67 httpsdoiorg101111j1365-2702200601852x

6 Sax H Perneger T Hugonnet S et al Knowledge of standard and isolationprecautions in a large teaching hospital Infect Control Hosp Epidemiol200526298ndash304 httpsdoiorg101086502543

7 Sax H Uckay I Richet H et al Determinants of good adherence to handhygiene among healthcare workers who have extensive exposure to handhygiene campaigns Infect Control Hosp Epidemiol 2007281267ndash74httpsdoiorg101086521663

8 Gurses AP Seidl KL Vaidya V et al Systems ambiguity and guidelinecompliance a qualitative study of how intensive care units follow evidence-based guidelines to reduce healthcare-associated infections Qual Saf HealthCare 200817351ndash9 httpsdoiorg101136qshc2006021709

9 Grundgeiger T Sanderson PM Orihuela CB et al Prospective memoryin the ICU the effect of visual cues on task execution in arepresentative simulation Ergonomics 201356579ndash89 httpsdoiorg101080001401392013765604

Fig 9 The final signage solution for combined precautions Legend These signs have been translated from German to English for publication

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 12 of 13

majority of participants the symbols for airborne isola-tion were sometimes incorrectly interpreted as meaningdroplet isolation The three variants with the highestcomprehensibility and least conflicting interpretationswere retained for use in further signage prototypes(Fig 7)

Iterative prototyping and evaluationThe process of iterative prototyping and evaluation of iso-lation signage occurred in parallel to the testing of sym-bols During this process several prototypes emerged withvarying levels of sophistication In the earliest stages ideaswere expressed on paper in the form of sketches Thosesketches with the most positive feedback from the targetpopulation were then transformed into more sophisticatedprototypes As prototypes were continually evaluatedthrough informal discussions with frontline HCPs theirfeedback provided insights that led to further refining ofconsecutive prototypes Experts in infection preventionand control were regularly consulted to ensure accuracyof the signage content This iterative design process asdocumented in Additional file 3 continued until satur-ation was achieved (ie until no new feedback was given)

Final signage solutionThe final solutions that resulted from the iterative proto-typing and evaluation process were shared with agraphic designer to produce the final signage system forthe three main isolation categories (Fig 8) as well as twosigns for combined precautions (Fig 9) This solutionfeatures a caution tape graphic and salient colours todraw attention to those entering the room that specialprecautions must be taken The isolation categories arecommunicated dually through the colour which is stan-dardised throughout all isolation precaution documentsand the prominent symbol portraying the transmissionpathway The specific precautions are portrayed in theorder in which they must be performed removing

method ambiguity The use of text is limited and thesignage relies largely on user-friendly graphics to sup-port comprehension regardless of language proficiencyThe signage is available for download on the intranetand can be printed with one sign per A4 sheet of paperBeyond the scope of the physical signage hospital guide-lines have also been introduced that limit the amountand type of information that can be posted on patientdoors which increases the saliency of remaining signageIn collaboration with the infection prevention depart-ment the housekeeping department has also revisedtheir isolation precaution guidelines and brochures toeliminate confusion with signage intended for HCPsThe signs were implemented by e-mailing heads of

wards to inform them of the new signage announce-ment and posting of the new signs on the intranet ser-ver and physically distributing printed signs to eachhospital ward according to number of beds Additionalcopies were made available for order Physical copiesand links to the previous signage were removed

DiscussionThis paper describes the successful application of a user-centred participatory design process to develop a sign-age system for communicating isolation precautionsThe resulting signage system aims to serve as a visualcue for HCPs remove ambiguity and elicit safe infectionprevention behaviours to ultimately prevent the trans-mission of infectious agentsOur analysis of existing isolation signage revealed that

ambiguity was indeed a major factor responsible fornon-compliance with transmission-based precautions inour hospital This is consistent with the findings ofGurses et al who propose systems ambiguity as aframework to explain procedural non-compliance inhealthcare [8] Ambiguity in our institution was identi-fied mainly in the form of task ambiguity (not knowingwhich guidelines are applicable for which patients) and

Table 1 Established personas (Continued)

Persona Description User requirements

at the USZ even picking up a Swiss German accentbull She has been working in the emergency ward for 12years now and although she has no medical trainingshe is excellent at what she does

Legend Personas fictional characters based on input from real users were established to understand the needs and goals of the individuals who will interactwith the signage system and to guide the subsequent design process

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 8 of 13

method ambiguity (not knowing how or in which orderto complete a particular guideline) This was due to thelack of indication about which category of isolation a pa-tient was under or which preventative measures wereapplicable To specifically address barriers related to taskand method ambiguity the new signage was designedwith the intent of bringing isolation guidelines directlyto the frontline where their use is indicated also re-ferred to as placing ldquoknowledge in the worldrdquo [23 24]The symbols and colour-scheme developed to portray

isolation categories (contact droplet and airborne) weredeemed to be an important part of the overall signagewith the intention that these may become standardisedthroughout the institution and thus increase recognitionand compliance The comprehensibility evaluation ofthese symbols revealed that the airborne and droplet iso-lation symbols were the most often confounded This isnot surprising due to the similar means by which bothairborne particles and droplets can be propelled into theenvironment through coughing and sneezing In orderto further distinguish these symbols they have beenassociated in the new signage with standardised colourscheme where airborne is blue droplet is green andcontact is orange The standardisation of these colourschemes is intended to further aid in the distinction ofdifferent isolation categories and make them quicklyrecognisable once they have been learned through re-peated exposure

Table 2 Identified design requirements

Functional requirements (what the system should do)

Informationdissemination

bull Draw the attention of anyone entering the room thatspecial precautions must be taken

bull Inform any person entering the patient room whatisolation status that patient has

bull Inform any person entering the patient room aboutthe isolation precautions they must employ accordingto the patientrsquos isolation status

Inform healthcare personnel about requiredpersonal protective equipment

Inform cleaning staff about required protectiveequipment adapted disinfectants and prioritisedcleaning measures

Inform visitors about required personal protectiveequipment or instruct them to see a staff member

bull Inform any person entering the room about the orderin which precautions (eg donning and doffingpersonal protective equipment hand hygiene) shouldbe performed

bull Inform anyone transporting the patient about thetransmission-based precautions that shouldbe respected

bull In addition to the three main categories oftransmission-based precautions (contact droplet andairborne) signage should also be designed tocommunicate combined or ldquolightrdquo isolationprecautions specific to the USZ

USZ guidelines bull Be consistent with USZ guidelines for isolationprecautions The three main isolationcategories include

Contact isolation don gown Droplet isolation don surgical mask Airborne isolation don FFP2 mask

bull Communicate combined isolation precautions Contact + Droplet isolation don gown andsurgical mask

Contact + Airborne isolation don gown andFFP2 mask

Non-functional requirements(constraints on the system and its development)

Maintenancerestraints

bull Must be easy to hang and remove on an as-need basisbull If printed on paper must either be laminate so that itmay be cleaned and reused or single use

Accessibilityandconfidentialityrequirements

bull Should include graphics and symbols to accommodatenon-native German speaking personnel

bull Signage should avoid potential patient stigmatisationand should not disclose any confidentialpatient information

bull Signage must be accessible to individuals with colourvision deficiency for example by avoiding problematiccolour combinations and employing both colours andsymbols to convey messages over multiple channels

Physicalenvironmentrequirements

bull Signage must be noticeable relative to other signs inthe healthcare setting(appropriate single-to-noise ratio)

bull Some indication of the patientrsquos isolation statusshould travel with the patient at all times so that theappropriate transmission-based precautions can becommunicated at all times (eg when the patient isoutside of the room where the sign is posted) ndash thiscould be attached to the patient herself or to thepatientrsquos bed

bull Signage for housekeeping personnel should be of aportable size (A4 or smaller) so that it can fit on thecleaning trolleys

Organisational bull The signage should be able to quickly communicate

Table 2 Identified design requirements (Continued)

environmentrequirements

the required actions so that healthcare providers donot need to slow down (lsquobreak the rhythmrsquo) tointerpret them

bull If sign will be paper-based it should be easilyaccessible to staff on the ward when an isolatedpatient arrives (eg printed copies from intranet)or purchasable

bull Any posted signs must be consistent with theCorporate Design Guidelines

bull Information communicated through signage must beconsistent with evidence based-guidelines such as theCDC 2007 guidance as well as institutional infectioncontrol guidelines

Technicalenvironmentrequirements

bull Colour printer must be available if units are to printtheir own copies of paper-based signage

bull Intranet connection must be available if units are todownload the signs

bull Staff must be able to post the signage either by usingan adhesive material or the signs may be printeddirectly onto an adhesive sheet

bull Handling of signage material should be cost-effectiveand practical in every-day use

bull It should be possible to update the signage systemeasily in case new hospital rulesguidelinesare introduced

Legend Design requirements identified during interviews and observationsserved as a guide to ensure that subsequent designs met user needs whilesatisfying functional and non-functional requirements USZ University HospitalZurich CDC Centers for Disease Control

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 9 of 13

It is commonly accepted that ldquoconcept-relatedrdquo sym-bols which are abstract representations of the referentor subject they represent require more training beforethey can be understood by viewers [25] However by de-signing symbols for isolation precaution signage suchthat they are consistent with mental models this projectaimed to achieve a design that requires minimal trainingand that may also be intuitively understood Interest-ingly comprehensibility testing revealed that symbolsshowing the whole human figure were rated higher thanthose without the human figure or with an abstract partof the human body (eg only hands) This finding is con-sistent with results of the Hablamos Juntos Report who

evaluated the usability of several symbols for use in way-finding signage in hospital settings and found that symbolswith the whole human body were best understood [12]In addition to comprehensibility benefits including

the human figure particularly human eyes may be im-portant as it relates to emotional design Multiple studieshave examined the effect of images of human eyes oncooperative behaviour such as an ldquohonour systemrdquomethod of payment to an honesty box to pay for drinksin a coffee room [26] Such studies have found that thepresence of eye images act as a subtle cue and thatpeople paid as much as three times more often for theirdrinks when human eyes were displayed as opposed to

Fig 5 Workshop example of ldquoforcing functionrdquo during ideation (left) and prototyping (right) phases Legend This extract from a design thinkingworkshop shows one participantrsquos proposal to use a ldquoforcing functionrdquo to ensure that hands are disinfected prior to entry The middle shows adoor handle that only opens when alcohol is detected The right shows a prototype featuring the forcing function of a mask suspended in thedoorway through which clinicians must walk and thereby don masks upon room entry

Fig 6 Idea (left) and Prototype (right) of signage from design thinking workshop Legend This prototype developed during a design thinkingworkshop sends a strong visual cue about the necessary precautions The sign reads ldquoWarning before entering helliprdquo

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 10 of 13

when a neutral control image was displayed [27] Studiesin infection prevention settings however have hadmixed success in reproducing this effect [28ndash30] Furtherstudies on this topic are warranted to better understandhow signage may be employed to prime cooperative be-haviour and thus improve guideline adherenceThe field of infection prevention and patient safety is

rife with opportunities to actively include HCPs in user-centred design processes to improve healthcare environ-ments and practises The participatory design approachwas well suited for this inquiry as it allowed us to activelyinvolve stakeholders with essential insights thereby estab-lishing ownership and increasing chances of acceptanceand sustainability of the new signage The benefits of col-laborating with frontline HCPs extend beyond the scopeof the resulting design to also improve the image of theInfection Control department as a resource and to nurturethe possibility of further collaboration Recent reviews onthe use of participatory approaches such as experience-based co-design or co-production in which patients andhealthcare staff are engaged to improve health servicesreport outcomes related to the value of patient and staffinvolvement the quantity and quality of ideas and sugges-tions to modify practices and tangible changes in servicedelivery and user experience [31 32]Some limitations of this study should be considered

During this study we were faced with the challenge of

changing institutional guidelines for isolation precau-tions This prevented a quantitative analysis of change inpractice and presented a challenge during the evaluationwith frontline staff who were not yet familiar with thenew guidelines and thus had a tendency to focus on thediscrepancies between the ldquonewrdquo vs the current guide-lines rather than signage design The latter was ad-dressed through discussion with participants about thepossibility of new evidence-based practices and also bypresenting frontline users with prototypes that were con-sistent with their existing mental models ie consistentwith current guidelines Also the introduction of suchsignage is intended to serve as a visual cue and to re-move ambiguity regarding which precautions should beused and when The introduction of such signage how-ever does not entirely remove other known barriers tocompliance with isolation precautions such as ldquolack oftimerdquo [33] or ldquoavailability of protective clothingrdquo [5] It isthus imperative that the introduction of such signagetakes place within the context of a systems approach en-suring for example that the necessary time and materialresources are also available in order to mitigate thesebarriers

ConclusionsIn conclusion this study resulted in a user-centred sign-age design solution and set of comprehensible symbols

Fig 7 Symbols for contact (left) droplet (middle) and airborne (right) isolation Legend The variants of each symbol with the highest judgementand comprehensibility ratings were retained for use in further signage development phases

Fig 8 The final signage solution for contact (left) droplet (middle) and airborne (right) isolation Legend The final solution to be printed withone sign per A4 sheet incorporates several features to satisfy the identified design requirements These signs have been translated from Germanto English for publication

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 11 of 13

to remove ambiguity and to make compliance withevidence-based guidelines easy and intuitive for HCPsand visitors to the USZ The introduction of signageparticularly for infection control offers a promising op-portunity to make guidelines available directly at thefrontline where their use is indicated thereby reducingthe need for training and standard operating proceduresThis article further describes the application of a user-centred participatory design process which has great po-tential for application in the field of hospital infectioncontrol to design solutions that make performing infec-tion prevention behaviours easy and intuitive

Supplementary informationSupplementary information accompanies this paper at httpsdoiorg101186s13756-019-0629-9

Additional file 1 Pictorial portrayal of isolation categories

Additional file 2 Results of Judgement and Comprehension testing

Additional file 3 Iterations of Isolation Signage System

AbbreviationsCDC Centers for Disease Control HAI Healthcare-associated infectionsHCP Healthcare provider ID Infectious diseases IPC Infection preventionand control USZ University Hospital Zurich

AcknowledgementsWe would like to warmly acknowledge all study participants We would alsolike to acknowledge Andreacute Rothfuchs of Studio Sirup who provided graphicdesign services for the final signage solution

Authorsrsquo contributionsLC and HS conceived and designed the study LC conducted data collectionanalysis and iterative signage design and evaluation MS MM and AWprovided iterative feedback to inform the final signage solution LC draftedthe manuscript and all authors provided detailed feedback and approvedthe final manuscript

FundingThis work was partially funded by the Swiss National Science Foundation(32003B_149474) and by the University Hospital of Zurich Department ofQuality Management and Patient Safety

Availability of data and materialsThe datasets used andor analysed during the current study are availablefrom the corresponding author on reasonable request

Ethics approval and consent to participateThe Zurich Cantonal Ethics Committee waived the need for formal ethicsreview of this project (KEK-StV-Nr 4114) Participation in all study activitieswas voluntary and participants were free to withdraw at any time Allinterview and workshop participants provided written informed consentprior to participation

Consent for publicationNot applicable

Competing interestsThe authors declare that they have no competing interests

Author details1Division of Infectious Diseases and Hospital Epidemiology UniversityHospital Zurich and University of Zurich Raemistrasse 100 HAL14 8091Zurich Switzerland 2Department of Management Technology andEconomics ETH Zurich Zurich Switzerland

Received 9 August 2019 Accepted 16 October 2019

References1 World Health Organization (WHO) Report on the burden of endemic health

care-associated infection wordwide Geneva World Health Organization2011

2 Siegel JD Rhinehard E Jackson M et al 2007 guideline for isolationprecautions preventing transmission of infectious agents in healthcaresettings 2007

3 Larson E Kretzer EK Compliance with handwashing and barrier precautionsJ Hosp Infect 199530(Suppl)88ndash106

4 Weber D Sickbert-Bennett EE Brown VM et al Compliance withisolation precautions at a university hospital Infect Control HospEpidemiol 200728358ndash61

5 Gammon J Morgan-Samuel H Gould D A review of the evidence forsuboptimal compliance of healthcare practitioners to standarduniversalinfection control precautions J Clin Nurs 200817157ndash67 httpsdoiorg101111j1365-2702200601852x

6 Sax H Perneger T Hugonnet S et al Knowledge of standard and isolationprecautions in a large teaching hospital Infect Control Hosp Epidemiol200526298ndash304 httpsdoiorg101086502543

7 Sax H Uckay I Richet H et al Determinants of good adherence to handhygiene among healthcare workers who have extensive exposure to handhygiene campaigns Infect Control Hosp Epidemiol 2007281267ndash74httpsdoiorg101086521663

8 Gurses AP Seidl KL Vaidya V et al Systems ambiguity and guidelinecompliance a qualitative study of how intensive care units follow evidence-based guidelines to reduce healthcare-associated infections Qual Saf HealthCare 200817351ndash9 httpsdoiorg101136qshc2006021709

9 Grundgeiger T Sanderson PM Orihuela CB et al Prospective memoryin the ICU the effect of visual cues on task execution in arepresentative simulation Ergonomics 201356579ndash89 httpsdoiorg101080001401392013765604

Fig 9 The final signage solution for combined precautions Legend These signs have been translated from German to English for publication

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 12 of 13

method ambiguity (not knowing how or in which orderto complete a particular guideline) This was due to thelack of indication about which category of isolation a pa-tient was under or which preventative measures wereapplicable To specifically address barriers related to taskand method ambiguity the new signage was designedwith the intent of bringing isolation guidelines directlyto the frontline where their use is indicated also re-ferred to as placing ldquoknowledge in the worldrdquo [23 24]The symbols and colour-scheme developed to portray

isolation categories (contact droplet and airborne) weredeemed to be an important part of the overall signagewith the intention that these may become standardisedthroughout the institution and thus increase recognitionand compliance The comprehensibility evaluation ofthese symbols revealed that the airborne and droplet iso-lation symbols were the most often confounded This isnot surprising due to the similar means by which bothairborne particles and droplets can be propelled into theenvironment through coughing and sneezing In orderto further distinguish these symbols they have beenassociated in the new signage with standardised colourscheme where airborne is blue droplet is green andcontact is orange The standardisation of these colourschemes is intended to further aid in the distinction ofdifferent isolation categories and make them quicklyrecognisable once they have been learned through re-peated exposure

Table 2 Identified design requirements

Functional requirements (what the system should do)

Informationdissemination

bull Draw the attention of anyone entering the room thatspecial precautions must be taken

bull Inform any person entering the patient room whatisolation status that patient has

bull Inform any person entering the patient room aboutthe isolation precautions they must employ accordingto the patientrsquos isolation status

Inform healthcare personnel about requiredpersonal protective equipment

Inform cleaning staff about required protectiveequipment adapted disinfectants and prioritisedcleaning measures

Inform visitors about required personal protectiveequipment or instruct them to see a staff member

bull Inform any person entering the room about the orderin which precautions (eg donning and doffingpersonal protective equipment hand hygiene) shouldbe performed

bull Inform anyone transporting the patient about thetransmission-based precautions that shouldbe respected

bull In addition to the three main categories oftransmission-based precautions (contact droplet andairborne) signage should also be designed tocommunicate combined or ldquolightrdquo isolationprecautions specific to the USZ

USZ guidelines bull Be consistent with USZ guidelines for isolationprecautions The three main isolationcategories include

Contact isolation don gown Droplet isolation don surgical mask Airborne isolation don FFP2 mask

bull Communicate combined isolation precautions Contact + Droplet isolation don gown andsurgical mask

Contact + Airborne isolation don gown andFFP2 mask

Non-functional requirements(constraints on the system and its development)

Maintenancerestraints

bull Must be easy to hang and remove on an as-need basisbull If printed on paper must either be laminate so that itmay be cleaned and reused or single use

Accessibilityandconfidentialityrequirements

bull Should include graphics and symbols to accommodatenon-native German speaking personnel

bull Signage should avoid potential patient stigmatisationand should not disclose any confidentialpatient information

bull Signage must be accessible to individuals with colourvision deficiency for example by avoiding problematiccolour combinations and employing both colours andsymbols to convey messages over multiple channels

Physicalenvironmentrequirements

bull Signage must be noticeable relative to other signs inthe healthcare setting(appropriate single-to-noise ratio)

bull Some indication of the patientrsquos isolation statusshould travel with the patient at all times so that theappropriate transmission-based precautions can becommunicated at all times (eg when the patient isoutside of the room where the sign is posted) ndash thiscould be attached to the patient herself or to thepatientrsquos bed

bull Signage for housekeeping personnel should be of aportable size (A4 or smaller) so that it can fit on thecleaning trolleys

Organisational bull The signage should be able to quickly communicate

Table 2 Identified design requirements (Continued)

environmentrequirements

the required actions so that healthcare providers donot need to slow down (lsquobreak the rhythmrsquo) tointerpret them

bull If sign will be paper-based it should be easilyaccessible to staff on the ward when an isolatedpatient arrives (eg printed copies from intranet)or purchasable

bull Any posted signs must be consistent with theCorporate Design Guidelines

bull Information communicated through signage must beconsistent with evidence based-guidelines such as theCDC 2007 guidance as well as institutional infectioncontrol guidelines

Technicalenvironmentrequirements

bull Colour printer must be available if units are to printtheir own copies of paper-based signage

bull Intranet connection must be available if units are todownload the signs

bull Staff must be able to post the signage either by usingan adhesive material or the signs may be printeddirectly onto an adhesive sheet

bull Handling of signage material should be cost-effectiveand practical in every-day use

bull It should be possible to update the signage systemeasily in case new hospital rulesguidelinesare introduced

Legend Design requirements identified during interviews and observationsserved as a guide to ensure that subsequent designs met user needs whilesatisfying functional and non-functional requirements USZ University HospitalZurich CDC Centers for Disease Control

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 9 of 13

It is commonly accepted that ldquoconcept-relatedrdquo sym-bols which are abstract representations of the referentor subject they represent require more training beforethey can be understood by viewers [25] However by de-signing symbols for isolation precaution signage suchthat they are consistent with mental models this projectaimed to achieve a design that requires minimal trainingand that may also be intuitively understood Interest-ingly comprehensibility testing revealed that symbolsshowing the whole human figure were rated higher thanthose without the human figure or with an abstract partof the human body (eg only hands) This finding is con-sistent with results of the Hablamos Juntos Report who

evaluated the usability of several symbols for use in way-finding signage in hospital settings and found that symbolswith the whole human body were best understood [12]In addition to comprehensibility benefits including

the human figure particularly human eyes may be im-portant as it relates to emotional design Multiple studieshave examined the effect of images of human eyes oncooperative behaviour such as an ldquohonour systemrdquomethod of payment to an honesty box to pay for drinksin a coffee room [26] Such studies have found that thepresence of eye images act as a subtle cue and thatpeople paid as much as three times more often for theirdrinks when human eyes were displayed as opposed to

Fig 5 Workshop example of ldquoforcing functionrdquo during ideation (left) and prototyping (right) phases Legend This extract from a design thinkingworkshop shows one participantrsquos proposal to use a ldquoforcing functionrdquo to ensure that hands are disinfected prior to entry The middle shows adoor handle that only opens when alcohol is detected The right shows a prototype featuring the forcing function of a mask suspended in thedoorway through which clinicians must walk and thereby don masks upon room entry

Fig 6 Idea (left) and Prototype (right) of signage from design thinking workshop Legend This prototype developed during a design thinkingworkshop sends a strong visual cue about the necessary precautions The sign reads ldquoWarning before entering helliprdquo

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 10 of 13

when a neutral control image was displayed [27] Studiesin infection prevention settings however have hadmixed success in reproducing this effect [28ndash30] Furtherstudies on this topic are warranted to better understandhow signage may be employed to prime cooperative be-haviour and thus improve guideline adherenceThe field of infection prevention and patient safety is

rife with opportunities to actively include HCPs in user-centred design processes to improve healthcare environ-ments and practises The participatory design approachwas well suited for this inquiry as it allowed us to activelyinvolve stakeholders with essential insights thereby estab-lishing ownership and increasing chances of acceptanceand sustainability of the new signage The benefits of col-laborating with frontline HCPs extend beyond the scopeof the resulting design to also improve the image of theInfection Control department as a resource and to nurturethe possibility of further collaboration Recent reviews onthe use of participatory approaches such as experience-based co-design or co-production in which patients andhealthcare staff are engaged to improve health servicesreport outcomes related to the value of patient and staffinvolvement the quantity and quality of ideas and sugges-tions to modify practices and tangible changes in servicedelivery and user experience [31 32]Some limitations of this study should be considered

During this study we were faced with the challenge of

changing institutional guidelines for isolation precau-tions This prevented a quantitative analysis of change inpractice and presented a challenge during the evaluationwith frontline staff who were not yet familiar with thenew guidelines and thus had a tendency to focus on thediscrepancies between the ldquonewrdquo vs the current guide-lines rather than signage design The latter was ad-dressed through discussion with participants about thepossibility of new evidence-based practices and also bypresenting frontline users with prototypes that were con-sistent with their existing mental models ie consistentwith current guidelines Also the introduction of suchsignage is intended to serve as a visual cue and to re-move ambiguity regarding which precautions should beused and when The introduction of such signage how-ever does not entirely remove other known barriers tocompliance with isolation precautions such as ldquolack oftimerdquo [33] or ldquoavailability of protective clothingrdquo [5] It isthus imperative that the introduction of such signagetakes place within the context of a systems approach en-suring for example that the necessary time and materialresources are also available in order to mitigate thesebarriers

ConclusionsIn conclusion this study resulted in a user-centred sign-age design solution and set of comprehensible symbols

Fig 7 Symbols for contact (left) droplet (middle) and airborne (right) isolation Legend The variants of each symbol with the highest judgementand comprehensibility ratings were retained for use in further signage development phases

Fig 8 The final signage solution for contact (left) droplet (middle) and airborne (right) isolation Legend The final solution to be printed withone sign per A4 sheet incorporates several features to satisfy the identified design requirements These signs have been translated from Germanto English for publication

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 11 of 13

to remove ambiguity and to make compliance withevidence-based guidelines easy and intuitive for HCPsand visitors to the USZ The introduction of signageparticularly for infection control offers a promising op-portunity to make guidelines available directly at thefrontline where their use is indicated thereby reducingthe need for training and standard operating proceduresThis article further describes the application of a user-centred participatory design process which has great po-tential for application in the field of hospital infectioncontrol to design solutions that make performing infec-tion prevention behaviours easy and intuitive

Supplementary informationSupplementary information accompanies this paper at httpsdoiorg101186s13756-019-0629-9

Additional file 1 Pictorial portrayal of isolation categories

Additional file 2 Results of Judgement and Comprehension testing

Additional file 3 Iterations of Isolation Signage System

AbbreviationsCDC Centers for Disease Control HAI Healthcare-associated infectionsHCP Healthcare provider ID Infectious diseases IPC Infection preventionand control USZ University Hospital Zurich

AcknowledgementsWe would like to warmly acknowledge all study participants We would alsolike to acknowledge Andreacute Rothfuchs of Studio Sirup who provided graphicdesign services for the final signage solution

Authorsrsquo contributionsLC and HS conceived and designed the study LC conducted data collectionanalysis and iterative signage design and evaluation MS MM and AWprovided iterative feedback to inform the final signage solution LC draftedthe manuscript and all authors provided detailed feedback and approvedthe final manuscript

FundingThis work was partially funded by the Swiss National Science Foundation(32003B_149474) and by the University Hospital of Zurich Department ofQuality Management and Patient Safety

Availability of data and materialsThe datasets used andor analysed during the current study are availablefrom the corresponding author on reasonable request

Ethics approval and consent to participateThe Zurich Cantonal Ethics Committee waived the need for formal ethicsreview of this project (KEK-StV-Nr 4114) Participation in all study activitieswas voluntary and participants were free to withdraw at any time Allinterview and workshop participants provided written informed consentprior to participation

Consent for publicationNot applicable

Competing interestsThe authors declare that they have no competing interests

Author details1Division of Infectious Diseases and Hospital Epidemiology UniversityHospital Zurich and University of Zurich Raemistrasse 100 HAL14 8091Zurich Switzerland 2Department of Management Technology andEconomics ETH Zurich Zurich Switzerland

Received 9 August 2019 Accepted 16 October 2019

References1 World Health Organization (WHO) Report on the burden of endemic health

care-associated infection wordwide Geneva World Health Organization2011

2 Siegel JD Rhinehard E Jackson M et al 2007 guideline for isolationprecautions preventing transmission of infectious agents in healthcaresettings 2007

3 Larson E Kretzer EK Compliance with handwashing and barrier precautionsJ Hosp Infect 199530(Suppl)88ndash106

4 Weber D Sickbert-Bennett EE Brown VM et al Compliance withisolation precautions at a university hospital Infect Control HospEpidemiol 200728358ndash61

5 Gammon J Morgan-Samuel H Gould D A review of the evidence forsuboptimal compliance of healthcare practitioners to standarduniversalinfection control precautions J Clin Nurs 200817157ndash67 httpsdoiorg101111j1365-2702200601852x

6 Sax H Perneger T Hugonnet S et al Knowledge of standard and isolationprecautions in a large teaching hospital Infect Control Hosp Epidemiol200526298ndash304 httpsdoiorg101086502543

7 Sax H Uckay I Richet H et al Determinants of good adherence to handhygiene among healthcare workers who have extensive exposure to handhygiene campaigns Infect Control Hosp Epidemiol 2007281267ndash74httpsdoiorg101086521663

8 Gurses AP Seidl KL Vaidya V et al Systems ambiguity and guidelinecompliance a qualitative study of how intensive care units follow evidence-based guidelines to reduce healthcare-associated infections Qual Saf HealthCare 200817351ndash9 httpsdoiorg101136qshc2006021709

9 Grundgeiger T Sanderson PM Orihuela CB et al Prospective memoryin the ICU the effect of visual cues on task execution in arepresentative simulation Ergonomics 201356579ndash89 httpsdoiorg101080001401392013765604

Fig 9 The final signage solution for combined precautions Legend These signs have been translated from German to English for publication

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 12 of 13

It is commonly accepted that ldquoconcept-relatedrdquo sym-bols which are abstract representations of the referentor subject they represent require more training beforethey can be understood by viewers [25] However by de-signing symbols for isolation precaution signage suchthat they are consistent with mental models this projectaimed to achieve a design that requires minimal trainingand that may also be intuitively understood Interest-ingly comprehensibility testing revealed that symbolsshowing the whole human figure were rated higher thanthose without the human figure or with an abstract partof the human body (eg only hands) This finding is con-sistent with results of the Hablamos Juntos Report who

evaluated the usability of several symbols for use in way-finding signage in hospital settings and found that symbolswith the whole human body were best understood [12]In addition to comprehensibility benefits including

the human figure particularly human eyes may be im-portant as it relates to emotional design Multiple studieshave examined the effect of images of human eyes oncooperative behaviour such as an ldquohonour systemrdquomethod of payment to an honesty box to pay for drinksin a coffee room [26] Such studies have found that thepresence of eye images act as a subtle cue and thatpeople paid as much as three times more often for theirdrinks when human eyes were displayed as opposed to

Fig 5 Workshop example of ldquoforcing functionrdquo during ideation (left) and prototyping (right) phases Legend This extract from a design thinkingworkshop shows one participantrsquos proposal to use a ldquoforcing functionrdquo to ensure that hands are disinfected prior to entry The middle shows adoor handle that only opens when alcohol is detected The right shows a prototype featuring the forcing function of a mask suspended in thedoorway through which clinicians must walk and thereby don masks upon room entry

Fig 6 Idea (left) and Prototype (right) of signage from design thinking workshop Legend This prototype developed during a design thinkingworkshop sends a strong visual cue about the necessary precautions The sign reads ldquoWarning before entering helliprdquo

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 10 of 13

when a neutral control image was displayed [27] Studiesin infection prevention settings however have hadmixed success in reproducing this effect [28ndash30] Furtherstudies on this topic are warranted to better understandhow signage may be employed to prime cooperative be-haviour and thus improve guideline adherenceThe field of infection prevention and patient safety is

rife with opportunities to actively include HCPs in user-centred design processes to improve healthcare environ-ments and practises The participatory design approachwas well suited for this inquiry as it allowed us to activelyinvolve stakeholders with essential insights thereby estab-lishing ownership and increasing chances of acceptanceand sustainability of the new signage The benefits of col-laborating with frontline HCPs extend beyond the scopeof the resulting design to also improve the image of theInfection Control department as a resource and to nurturethe possibility of further collaboration Recent reviews onthe use of participatory approaches such as experience-based co-design or co-production in which patients andhealthcare staff are engaged to improve health servicesreport outcomes related to the value of patient and staffinvolvement the quantity and quality of ideas and sugges-tions to modify practices and tangible changes in servicedelivery and user experience [31 32]Some limitations of this study should be considered

During this study we were faced with the challenge of

changing institutional guidelines for isolation precau-tions This prevented a quantitative analysis of change inpractice and presented a challenge during the evaluationwith frontline staff who were not yet familiar with thenew guidelines and thus had a tendency to focus on thediscrepancies between the ldquonewrdquo vs the current guide-lines rather than signage design The latter was ad-dressed through discussion with participants about thepossibility of new evidence-based practices and also bypresenting frontline users with prototypes that were con-sistent with their existing mental models ie consistentwith current guidelines Also the introduction of suchsignage is intended to serve as a visual cue and to re-move ambiguity regarding which precautions should beused and when The introduction of such signage how-ever does not entirely remove other known barriers tocompliance with isolation precautions such as ldquolack oftimerdquo [33] or ldquoavailability of protective clothingrdquo [5] It isthus imperative that the introduction of such signagetakes place within the context of a systems approach en-suring for example that the necessary time and materialresources are also available in order to mitigate thesebarriers

ConclusionsIn conclusion this study resulted in a user-centred sign-age design solution and set of comprehensible symbols

Fig 7 Symbols for contact (left) droplet (middle) and airborne (right) isolation Legend The variants of each symbol with the highest judgementand comprehensibility ratings were retained for use in further signage development phases

Fig 8 The final signage solution for contact (left) droplet (middle) and airborne (right) isolation Legend The final solution to be printed withone sign per A4 sheet incorporates several features to satisfy the identified design requirements These signs have been translated from Germanto English for publication

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 11 of 13

to remove ambiguity and to make compliance withevidence-based guidelines easy and intuitive for HCPsand visitors to the USZ The introduction of signageparticularly for infection control offers a promising op-portunity to make guidelines available directly at thefrontline where their use is indicated thereby reducingthe need for training and standard operating proceduresThis article further describes the application of a user-centred participatory design process which has great po-tential for application in the field of hospital infectioncontrol to design solutions that make performing infec-tion prevention behaviours easy and intuitive

Supplementary informationSupplementary information accompanies this paper at httpsdoiorg101186s13756-019-0629-9

Additional file 1 Pictorial portrayal of isolation categories

Additional file 2 Results of Judgement and Comprehension testing

Additional file 3 Iterations of Isolation Signage System

AbbreviationsCDC Centers for Disease Control HAI Healthcare-associated infectionsHCP Healthcare provider ID Infectious diseases IPC Infection preventionand control USZ University Hospital Zurich

AcknowledgementsWe would like to warmly acknowledge all study participants We would alsolike to acknowledge Andreacute Rothfuchs of Studio Sirup who provided graphicdesign services for the final signage solution

Authorsrsquo contributionsLC and HS conceived and designed the study LC conducted data collectionanalysis and iterative signage design and evaluation MS MM and AWprovided iterative feedback to inform the final signage solution LC draftedthe manuscript and all authors provided detailed feedback and approvedthe final manuscript

FundingThis work was partially funded by the Swiss National Science Foundation(32003B_149474) and by the University Hospital of Zurich Department ofQuality Management and Patient Safety

Availability of data and materialsThe datasets used andor analysed during the current study are availablefrom the corresponding author on reasonable request

Ethics approval and consent to participateThe Zurich Cantonal Ethics Committee waived the need for formal ethicsreview of this project (KEK-StV-Nr 4114) Participation in all study activitieswas voluntary and participants were free to withdraw at any time Allinterview and workshop participants provided written informed consentprior to participation

Consent for publicationNot applicable

Competing interestsThe authors declare that they have no competing interests

Author details1Division of Infectious Diseases and Hospital Epidemiology UniversityHospital Zurich and University of Zurich Raemistrasse 100 HAL14 8091Zurich Switzerland 2Department of Management Technology andEconomics ETH Zurich Zurich Switzerland

Received 9 August 2019 Accepted 16 October 2019

References1 World Health Organization (WHO) Report on the burden of endemic health

care-associated infection wordwide Geneva World Health Organization2011

2 Siegel JD Rhinehard E Jackson M et al 2007 guideline for isolationprecautions preventing transmission of infectious agents in healthcaresettings 2007

3 Larson E Kretzer EK Compliance with handwashing and barrier precautionsJ Hosp Infect 199530(Suppl)88ndash106

4 Weber D Sickbert-Bennett EE Brown VM et al Compliance withisolation precautions at a university hospital Infect Control HospEpidemiol 200728358ndash61

5 Gammon J Morgan-Samuel H Gould D A review of the evidence forsuboptimal compliance of healthcare practitioners to standarduniversalinfection control precautions J Clin Nurs 200817157ndash67 httpsdoiorg101111j1365-2702200601852x

6 Sax H Perneger T Hugonnet S et al Knowledge of standard and isolationprecautions in a large teaching hospital Infect Control Hosp Epidemiol200526298ndash304 httpsdoiorg101086502543

7 Sax H Uckay I Richet H et al Determinants of good adherence to handhygiene among healthcare workers who have extensive exposure to handhygiene campaigns Infect Control Hosp Epidemiol 2007281267ndash74httpsdoiorg101086521663

8 Gurses AP Seidl KL Vaidya V et al Systems ambiguity and guidelinecompliance a qualitative study of how intensive care units follow evidence-based guidelines to reduce healthcare-associated infections Qual Saf HealthCare 200817351ndash9 httpsdoiorg101136qshc2006021709

9 Grundgeiger T Sanderson PM Orihuela CB et al Prospective memoryin the ICU the effect of visual cues on task execution in arepresentative simulation Ergonomics 201356579ndash89 httpsdoiorg101080001401392013765604

Fig 9 The final signage solution for combined precautions Legend These signs have been translated from German to English for publication

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 12 of 13

when a neutral control image was displayed [27] Studiesin infection prevention settings however have hadmixed success in reproducing this effect [28ndash30] Furtherstudies on this topic are warranted to better understandhow signage may be employed to prime cooperative be-haviour and thus improve guideline adherenceThe field of infection prevention and patient safety is

rife with opportunities to actively include HCPs in user-centred design processes to improve healthcare environ-ments and practises The participatory design approachwas well suited for this inquiry as it allowed us to activelyinvolve stakeholders with essential insights thereby estab-lishing ownership and increasing chances of acceptanceand sustainability of the new signage The benefits of col-laborating with frontline HCPs extend beyond the scopeof the resulting design to also improve the image of theInfection Control department as a resource and to nurturethe possibility of further collaboration Recent reviews onthe use of participatory approaches such as experience-based co-design or co-production in which patients andhealthcare staff are engaged to improve health servicesreport outcomes related to the value of patient and staffinvolvement the quantity and quality of ideas and sugges-tions to modify practices and tangible changes in servicedelivery and user experience [31 32]Some limitations of this study should be considered

During this study we were faced with the challenge of

changing institutional guidelines for isolation precau-tions This prevented a quantitative analysis of change inpractice and presented a challenge during the evaluationwith frontline staff who were not yet familiar with thenew guidelines and thus had a tendency to focus on thediscrepancies between the ldquonewrdquo vs the current guide-lines rather than signage design The latter was ad-dressed through discussion with participants about thepossibility of new evidence-based practices and also bypresenting frontline users with prototypes that were con-sistent with their existing mental models ie consistentwith current guidelines Also the introduction of suchsignage is intended to serve as a visual cue and to re-move ambiguity regarding which precautions should beused and when The introduction of such signage how-ever does not entirely remove other known barriers tocompliance with isolation precautions such as ldquolack oftimerdquo [33] or ldquoavailability of protective clothingrdquo [5] It isthus imperative that the introduction of such signagetakes place within the context of a systems approach en-suring for example that the necessary time and materialresources are also available in order to mitigate thesebarriers

ConclusionsIn conclusion this study resulted in a user-centred sign-age design solution and set of comprehensible symbols

Fig 7 Symbols for contact (left) droplet (middle) and airborne (right) isolation Legend The variants of each symbol with the highest judgementand comprehensibility ratings were retained for use in further signage development phases

Fig 8 The final signage solution for contact (left) droplet (middle) and airborne (right) isolation Legend The final solution to be printed withone sign per A4 sheet incorporates several features to satisfy the identified design requirements These signs have been translated from Germanto English for publication

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 11 of 13

to remove ambiguity and to make compliance withevidence-based guidelines easy and intuitive for HCPsand visitors to the USZ The introduction of signageparticularly for infection control offers a promising op-portunity to make guidelines available directly at thefrontline where their use is indicated thereby reducingthe need for training and standard operating proceduresThis article further describes the application of a user-centred participatory design process which has great po-tential for application in the field of hospital infectioncontrol to design solutions that make performing infec-tion prevention behaviours easy and intuitive

Supplementary informationSupplementary information accompanies this paper at httpsdoiorg101186s13756-019-0629-9

Additional file 1 Pictorial portrayal of isolation categories

Additional file 2 Results of Judgement and Comprehension testing

Additional file 3 Iterations of Isolation Signage System

AbbreviationsCDC Centers for Disease Control HAI Healthcare-associated infectionsHCP Healthcare provider ID Infectious diseases IPC Infection preventionand control USZ University Hospital Zurich

AcknowledgementsWe would like to warmly acknowledge all study participants We would alsolike to acknowledge Andreacute Rothfuchs of Studio Sirup who provided graphicdesign services for the final signage solution

Authorsrsquo contributionsLC and HS conceived and designed the study LC conducted data collectionanalysis and iterative signage design and evaluation MS MM and AWprovided iterative feedback to inform the final signage solution LC draftedthe manuscript and all authors provided detailed feedback and approvedthe final manuscript

FundingThis work was partially funded by the Swiss National Science Foundation(32003B_149474) and by the University Hospital of Zurich Department ofQuality Management and Patient Safety

Availability of data and materialsThe datasets used andor analysed during the current study are availablefrom the corresponding author on reasonable request

Ethics approval and consent to participateThe Zurich Cantonal Ethics Committee waived the need for formal ethicsreview of this project (KEK-StV-Nr 4114) Participation in all study activitieswas voluntary and participants were free to withdraw at any time Allinterview and workshop participants provided written informed consentprior to participation

Consent for publicationNot applicable

Competing interestsThe authors declare that they have no competing interests

Author details1Division of Infectious Diseases and Hospital Epidemiology UniversityHospital Zurich and University of Zurich Raemistrasse 100 HAL14 8091Zurich Switzerland 2Department of Management Technology andEconomics ETH Zurich Zurich Switzerland

Received 9 August 2019 Accepted 16 October 2019

References1 World Health Organization (WHO) Report on the burden of endemic health

care-associated infection wordwide Geneva World Health Organization2011

2 Siegel JD Rhinehard E Jackson M et al 2007 guideline for isolationprecautions preventing transmission of infectious agents in healthcaresettings 2007

3 Larson E Kretzer EK Compliance with handwashing and barrier precautionsJ Hosp Infect 199530(Suppl)88ndash106

4 Weber D Sickbert-Bennett EE Brown VM et al Compliance withisolation precautions at a university hospital Infect Control HospEpidemiol 200728358ndash61

5 Gammon J Morgan-Samuel H Gould D A review of the evidence forsuboptimal compliance of healthcare practitioners to standarduniversalinfection control precautions J Clin Nurs 200817157ndash67 httpsdoiorg101111j1365-2702200601852x

6 Sax H Perneger T Hugonnet S et al Knowledge of standard and isolationprecautions in a large teaching hospital Infect Control Hosp Epidemiol200526298ndash304 httpsdoiorg101086502543

7 Sax H Uckay I Richet H et al Determinants of good adherence to handhygiene among healthcare workers who have extensive exposure to handhygiene campaigns Infect Control Hosp Epidemiol 2007281267ndash74httpsdoiorg101086521663

8 Gurses AP Seidl KL Vaidya V et al Systems ambiguity and guidelinecompliance a qualitative study of how intensive care units follow evidence-based guidelines to reduce healthcare-associated infections Qual Saf HealthCare 200817351ndash9 httpsdoiorg101136qshc2006021709

9 Grundgeiger T Sanderson PM Orihuela CB et al Prospective memoryin the ICU the effect of visual cues on task execution in arepresentative simulation Ergonomics 201356579ndash89 httpsdoiorg101080001401392013765604

Fig 9 The final signage solution for combined precautions Legend These signs have been translated from German to English for publication

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 12 of 13

to remove ambiguity and to make compliance withevidence-based guidelines easy and intuitive for HCPsand visitors to the USZ The introduction of signageparticularly for infection control offers a promising op-portunity to make guidelines available directly at thefrontline where their use is indicated thereby reducingthe need for training and standard operating proceduresThis article further describes the application of a user-centred participatory design process which has great po-tential for application in the field of hospital infectioncontrol to design solutions that make performing infec-tion prevention behaviours easy and intuitive

Supplementary informationSupplementary information accompanies this paper at httpsdoiorg101186s13756-019-0629-9

Additional file 1 Pictorial portrayal of isolation categories

Additional file 2 Results of Judgement and Comprehension testing

Additional file 3 Iterations of Isolation Signage System

AbbreviationsCDC Centers for Disease Control HAI Healthcare-associated infectionsHCP Healthcare provider ID Infectious diseases IPC Infection preventionand control USZ University Hospital Zurich

AcknowledgementsWe would like to warmly acknowledge all study participants We would alsolike to acknowledge Andreacute Rothfuchs of Studio Sirup who provided graphicdesign services for the final signage solution

Authorsrsquo contributionsLC and HS conceived and designed the study LC conducted data collectionanalysis and iterative signage design and evaluation MS MM and AWprovided iterative feedback to inform the final signage solution LC draftedthe manuscript and all authors provided detailed feedback and approvedthe final manuscript

FundingThis work was partially funded by the Swiss National Science Foundation(32003B_149474) and by the University Hospital of Zurich Department ofQuality Management and Patient Safety

Availability of data and materialsThe datasets used andor analysed during the current study are availablefrom the corresponding author on reasonable request

Ethics approval and consent to participateThe Zurich Cantonal Ethics Committee waived the need for formal ethicsreview of this project (KEK-StV-Nr 4114) Participation in all study activitieswas voluntary and participants were free to withdraw at any time Allinterview and workshop participants provided written informed consentprior to participation

Consent for publicationNot applicable

Competing interestsThe authors declare that they have no competing interests

Author details1Division of Infectious Diseases and Hospital Epidemiology UniversityHospital Zurich and University of Zurich Raemistrasse 100 HAL14 8091Zurich Switzerland 2Department of Management Technology andEconomics ETH Zurich Zurich Switzerland

Received 9 August 2019 Accepted 16 October 2019

References1 World Health Organization (WHO) Report on the burden of endemic health

care-associated infection wordwide Geneva World Health Organization2011

2 Siegel JD Rhinehard E Jackson M et al 2007 guideline for isolationprecautions preventing transmission of infectious agents in healthcaresettings 2007

3 Larson E Kretzer EK Compliance with handwashing and barrier precautionsJ Hosp Infect 199530(Suppl)88ndash106

4 Weber D Sickbert-Bennett EE Brown VM et al Compliance withisolation precautions at a university hospital Infect Control HospEpidemiol 200728358ndash61

5 Gammon J Morgan-Samuel H Gould D A review of the evidence forsuboptimal compliance of healthcare practitioners to standarduniversalinfection control precautions J Clin Nurs 200817157ndash67 httpsdoiorg101111j1365-2702200601852x

6 Sax H Perneger T Hugonnet S et al Knowledge of standard and isolationprecautions in a large teaching hospital Infect Control Hosp Epidemiol200526298ndash304 httpsdoiorg101086502543

7 Sax H Uckay I Richet H et al Determinants of good adherence to handhygiene among healthcare workers who have extensive exposure to handhygiene campaigns Infect Control Hosp Epidemiol 2007281267ndash74httpsdoiorg101086521663

8 Gurses AP Seidl KL Vaidya V et al Systems ambiguity and guidelinecompliance a qualitative study of how intensive care units follow evidence-based guidelines to reduce healthcare-associated infections Qual Saf HealthCare 200817351ndash9 httpsdoiorg101136qshc2006021709

9 Grundgeiger T Sanderson PM Orihuela CB et al Prospective memoryin the ICU the effect of visual cues on task execution in arepresentative simulation Ergonomics 201356579ndash89 httpsdoiorg101080001401392013765604

Fig 9 The final signage solution for combined precautions Legend These signs have been translated from German to English for publication

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 12 of 13

10 Gurses AP Ozok AA Pronovost PJ Time to accelerate integration of humanfactors and ergonomics in patient safety BMJ Qual Saf 201221347ndash51httpsdoiorg101136bmjqs-2011-000421

11 Olmstead WT The usability of symbols for Health care facilities the effectsof culture gender and age In Zwaga H Boersma T Hoonhout H editorsVisual information for everyday use design and research perspectivesLondon CRC Press 1998 p 315ndash20

12 Rousek JB Hallbeck MS Improving and analyzing signage within ahealthcare setting Appl Ergon 201142771ndash84 httpsdoiorg101016japergo201012004

13 Nevo I Fitzpatrick M Thomas RE et al The efficacy of visual cues toimprove hand hygiene compliance Simul Healthc 20105325ndash31 httpsdoiorg101097SIH0b013e3181f69482

14 Haines HM Wilson JR Health GB et al Development of a framework forparticipatory ergonomics Norwich HSE Books 1998

15 Clemensen J Larsen SB Kyng M et al Participatory design in healthsciences using cooperative experimental methods in developing healthservices and computer technology Qual Health Res 200717122ndash30 httpsdoiorg1011771049732306293664

16 Rogers Y Sharp H Preece J Interaction design beyond human-computerinteraction 3rd ed Chichester Wiley 2011pxv p 585

17 Nielsen L Personas-user focused design London Springer 201318 Plattner H Design thinking bootcamp bootleg Palo Alto Design School

Stanford 201019 Paper [Software] FiftyThree Inc 201320 Adobe Illustrator CC Computer software San Jose Adobe Systems

Inc 201421 Pernice K UX prototypes low Fidelity vs high Fidelity 2016 httpswww

nngroupcomarticlesux-prototype-hi-lo-fidelity (Accessed 7 Sept 2019)22 ISO 9186 Graphical Symbols - Test Methods Part 1 Method for testing

comprehensibility Accessed 7 Aug 201923 Norman DA The design of everyday things revised and expanded edition

New York Basic books 201324 Norman DA Cognition in the head and in the world an introduction to the

special issue on situated action Cognit Sci 1993171ndash6 httpsdoiorg101207s15516709cog1701_1

25 ISO 7001 Public information symbols Accessed 7 Aug 201926 Ernest-Jones M Nettle D Bateson M Effects of eye images on everyday

cooperative behavior a field experiment Evol Hum Behav 201132172ndash8httpsdoiorg101016jevolhumbehav201010006

27 Bateson M Nettle D Roberts G Cues of being watched enhancecooperation in a real-world setting Biol Lett 20062412ndash4 httpsdoiorg101098rsbl20060509

28 Stella SA Stace RJ Knepper BC et al The effect of eye images and a socialnorms message on healthcare provider hand hygiene adherence InfectControl Hosp Epidemiol 201940748ndash54 httpsdoiorg101017ice2019103

29 King D Vlaev I Everett-Thomas R et al ldquoPrimingrdquo hand hygiene compliancein clinical environments Health Psychol 20163596

30 Beyfus TA Dawson NL Danner CH et al The use of passive visual stimuli toenhance compliance with handwashing in a perioperative setting Am JInfect Control 201644496ndash9

31 Clarke D Jones F Harris R et al What outcomes are associated withdeveloping and implementing co-produced interventions in acutehealthcare settings A rapid evidence synthesis BMJ Open 20177e014650httpsdoiorg101136bmjopen-2016-014650J

32 Green T Bonner A Teleni L et al Use and reporting of experience-basedcodesign studies in the healthcare setting a systematic review BMJ QualSaf 2019 httpsdoiorg101136bmjqs-2019-009570J

33 Pittet D Mourouga P Perneger TV Compliance with handwashing in ateaching hospital Ann Intern Med 1999130126ndash30 httpsdoiorg1073260003-4819-130-2-199901190-00006

Publisherrsquos NoteSpringer Nature remains neutral with regard to jurisdictional claims inpublished maps and institutional affiliations

Clack et al Antimicrobial Resistance and Infection Control (2019) 8179 Page 13 of 13