Usability 101: The Principles of Usability

Engineering

Tuesday, August 6, 2002

Agenda

• Discuss the value of user-centered design• Describe the user-centered design and usability

engineering lifecycle• Discuss the usability testing process

Who We Are

• Communication Technologies Branch (CTB) – National Cancer Institute’s Office of Communications

• CTB Mission– To analyze, design, evaluate, and test communications

technology systems, (Web sites, software, mobile technologies) to make them more usable, useful, and accessible

Why We Do It• Failure of Web sites

– Users find information they’re seeking on Web sites only 42% of the time (Spool study of 15 large commercial sites)

– Only 51% of sites complied with simple Web usability principles (Forrester study of 20 major sites)

– Sixty-two percent of web shoppers gave up looking for an item (Zona study)

Traditional Development Process

How We Do It

• Usability Engineering– An evidence-based methodology that involves end users

in the design, testing, and evaluation processes to produce information systems that are measurably easier to use, learn, and remember

– Process involves:• Data collection about users’ needs/wants/behavior• Prototype development• Usability testing• Iterative design/usability testing

How We Do It• Research-Based Approach

– This approach applies the latest design and testing research to the development of communication technology systems, products, and services

– Modeled after the scientific community’s movement toward “evidence-based” medicine/science

– Involves a review of the research data related to Web design, usability, accessibility, and more

– Identifies gaps in the research – many areas have yet to be studied

Why We Do It• Usability Engineering Works

– It’s user-centric (not developer-centric)– It’s based on data, not opinions– It’s testable and verifiable– It’s performance-driven– Saves money and time

• Research-based Information Design Works– Removes much of the controversy in opinion– Performance oriented – measurably better/faster/etc.– Takes the guesswork out – allows you to focus on what

you don’t know – to solve problems

Usability Engineering Process

• Steps in the process– Planning– Gathering user data– Analyzing data– Translating data into design– Designing initial prototypes– Testing prototypes– Refining prototypes, retesting, retesting…

Planning• Planning Steps

– Define purpose / vision for the site– Develop measurable business objectives & user goals– Define primary / secondary audiences– Determine measurable usability objectives– Discuss expectations and requirements– Timeline and project plan

Planning

1. What is the purpose of the site? – Why are we building a site? – What are the goals of the site?

2. Why are we developing a web site? – What does success look like? – How will we know when we have been successful?

3. Who are we developing the site for? – Who is the site for? (User characteristics)– Why will they come to the site? (User needs, interests and goals)– When/where will they access the site? (User environment)– What will they do on the site? (User tasks and priorities of tasks)

Planning

4. What are our usability objectives? – Effectively (Ability to accomplish tasks)

– Efficiently (Ability to accomplish with speed and ease)

– Satisfying (Pleasing to users)

5. What are project team’s preferences?– Is there a vision of what the site will do and/or look like? – Are there any restraints or mandates for the site? – Are there any web site styles you prefer?

6. Timeline and Project Plan

Planning• Difference between business vs. user goals

– E-Commerce Sites• To generate revenue • To research products and prices

– Intranets• Improve employee communication• Get work done fast

– Information-Based Sites• To provide evidence-based research information• To find information

• Methods of Data Collection– Personal Interviews– Contextual Inquiries– Focus Groups– Surveys– Support Line/Phone Calls– E-mail– Web Logs

Gather User Data

• What is it?– Discussion with users to learn about their goals, tasks

and environment

• How to do it?– Use open-ended questions– Probe on problems – Do not give positive or negative signals

• Benefits/Disadvantages?– Learning from users first-hand– Users do not always recall processes accurately– What users say and do are not always the same

Personal Interviews

• What is it?– Observational method– Improves understanding of existing processes and steps

• How to do it?– Observe users in their natural environment– Observe users carrying out tasks, naturally– Do not give positive or negative signals

• Benefits/Disadvantages?– Relies on observation, not users’ recollection– Gather data users may not be able to vocalize– Time-consuming

Contextual Inquiries

"Which of the following best describes you?"

CancerNet NCI N % N %

Family/Friends 169 28 414 27Cancer Patients 85 14 266 17Educators/Students - - 155 10Researchers/Scientist 41 7 97 6Nurse (non- Oncology) 15 2 42 3Oncology Nurse 14 2 34 2Oncologist 60 10 33 2Physician (non- Oncology) 22 4 32 2J ournalist/Media Professional - - 31 2Librarian 29 5 30 2Patient Advocate 8 1 26 2Other 91 15 209 14Not specified 81 13 157 10

615 1526

Surveys

"What information are you looking for?"

Major Categories CancerNet NCI

I nformation on specific type of cancer 23% 25%Treatment information 19 17Symptoms, causes, risk factors….. 8 5Statistics (e.g. incidence rates, survival) 3 5Clinical Trials 11 5Access to other resources (e.g. treatment facilities, physicians) 3 4Drug information 3 4NI H Organization (e.g. mission, employment) - 3New treatments 5 3Ordering NCI publications 2 3Recent findings - 2Type of tumor (not by cancer name) 7 2Cancer literature 5 1Patient support 4 2Side eff ects 3 2

Surveys

Gather User Data• Need to design for user not let user design for you

• We’re developing a website. What tasks would you like to be able to do on a website for health communications planning? What would you like to be able to find?

• What are the four most important steps in planning a health communication campaign? What are some challenges you encounter when planning campaigns?

• Users have limited amount of technical knowledge

Translating Data into Design

• User Profiles / Personas– Characteristics about user, environment, and tasks– List or narrative

• Task Analysis– Lists of tasks prioritized by frequency and importance– Process Flows

• User and Site Goals– List of measurable goals

• Design Considerations– Guidelines based in research– User considerations

User Profile or Persona1. User Characteristics2. Environmental Characteristics3. Goal & Task Characteristics

User Profile or Persona• User Characteristics

– Demographics • age• gender• ethnicity• income• language• disability• occupation• education• learning needs• internet/computer experience

User Profile or Persona• Environment Characteristics

– Location• home/work• indoor/outdoor

– Workspace • cramped/spacious• bright/dim lighting

– Hardware • monitor size• connection speed• video/sound card

– Software • browser• resolution• plug-ins

User Profile or Persona• Goals / Tasks Characteristics

– Tasks• information-based• functionality-oriented

– Number• how many

– Flow• order of tasks

– Importance • most to least

– Frequency• most to least

Sarah Parker

Sarah is a Senior Marketing Specialist with seven years of experience planning health campaigns.

She works in a large office where she handles multiple projects. She is constantly busy and struggles with a limited budget.

Sarah can easily identify the steps necessary to carry out each project. She doesn’t need help determining how to approach the planning process and mainly uses the various resources available as a reference.

Sarah would appreciate any tool or resource that could help her get her work done faster and more efficiently.

User Persona

Maria Green

Maria is a junior specialist and is relatively new to the health communication planning field.

Although Maria faces many of the same challenges as Sarah, including lack of time, constrained budgets, insufficient support, she has less experience than Sarah.

Unlike Sarah, Maria does not have any formal training in planning and is less familiar with the steps required to develop a plan. Maria relies heavily on resources to help with her work.

She currently used an interactive tool, but has an older computer that cannot handle all of the features in the program. In addition, Maria has a very slow internet connection which limits the resources she can access online.

User Personas

• Task List– Lists of tasks prioritized by frequency and importance

• Task Flow Diagrams– Drawings that show tasks in the order performed

• Task Scenarios– Narrative descriptions of a task

• User and Task Matrix– Matrices that show which users perform which tasks

Task Analysis

User Goals

• Efficiency– How well should the user be able to perform?

• Within a certain time• With a certain degree of accuracy (error rates)• For a certain percentage of users

• Learning– How long should it take a user to learn the interface? – After not using the interface for awhile, how long should it

take for the user to get back up to speed?

• Satisfaction– How will the interface avoid inducing user boredom,

discomfort, frustration, or work overload?

User & Site Goals• Measurable Success Factors for the Site

– Increase revenue generated by the site by __% by ___. – Increase number of registered users by __% by ___. – Reduce number of customer service calls from ___ to ___ by

___.

• Measurable Success Factors for Users– 75% of all users will be able to load the software correctly on

the first attempt in less than 10 minutes.– 75% of users will be able to successfully locate the “Contact

Us” page on the web site with a minimum of two incorrect clicks and in less then 2 minutes.

– 75% of user will have a satisfaction rating of 7 or above (on a 10-point scale) after using the site for the first time.

• Based on needs of users, e.g.,– Priority of tasks and content– Organization of information, taxonomies, labeling– Font size, color palette, contrast, legibility, – Writing style and level– Layout, screen density– Complexity, accelerators– Training, help, tooltips, error management

Design the Initial Prototype

• Guidelines based on research – Enhance scanning by providing clear links, headings,

short phrases and sentences, and short paragraphs – Provide most important information at highest point on

page– Don’t rely on expert evaluations (heuristic reviews) to fix

site problems– Use parallel design to create prototypes

• Research-based Web design & usability site– http://usability.gov/research

Designing the Initial Prototype

Usability Defined• Usefulness

– Degree to which users can successfully achieve goals

• Effectiveness (ease of use)– Ability of users to accomplish goals with speed & ease

• Learnability– Ability to operate the system to some defined level of

competence after some predetermined amount/period of training

• Satisfaction / Likeability– Attitude of users, includes perceptions, feelings and

opinions of the product

Booth, Paul. An Introduction to Human-Computer Interaction. London: Lawrence Erlbaum Associates, 1989.

Usability Testing

• Planning– Define goals– Determine who will participate– Select appropriate tasks– Plan logistics

• Conducting– Assign roles– Collect data

• Analyzing & implementing results– Prioritize findings– Implement & retest

Usability Testing

• Define usability goals– Performance

• Measurements– speed– errors / success– learning, training time

– Preference• Measurements

– user satisfaction

• Determine who will participate– User profiles

• Match characteristics from user analysis• Select representative group of users

– Selecting participants• Recruiting – recruitment firms, databases, conferences• Numbers – target numbers, floaters• Schedule – allow recoup time• Pre-Questionnaires – profile of participants• Incentives – consent & payment form

Usability Testing

• Select Appropriate Tasks– Task List

• Prioritize by– Frequency– Importance– Vulnerability– Readiness

• Ensure each task is measurable. Define measures ahead of time

• Include pathway information for observers• Conduct pilot test to look for give-away wording or

confusing scenarios

Usability Testing

Usability Testing

• Create Scenarios– Find two clinical trials that relate to breast cancer

prevention– View a demonstration of how this site works– Create an account on this site– What are today’s rates for a 25-year fixed-rate

mortgage?

Usability Testing

• Plan Logistics– Test location

• Lab, office, usability / market research facility– Prepare for observers

• One-way glass observation room• Projected onto screen in adjoining room

– Traffic flow of participants– Audio & video recording

• Value of highlight tape

Usability Testing• Plan Logistics

– Materials needed• Screening questionnaire• Background questionnaire• Pre- and Post-test questionnaires• Video release form• Incentive signature form • Schedule• Facilitator’s guide• Participants’ scenarios• Observers’ scenarios (with pathways included)

• Data collection materials (with measurements defined)

Usability Testing

• Assigning roles– Facilitator

• Next to participant or in adjoining room• Role (see handout)

– Observers• Role (see handout)

Usability Testing

Video Highlight Tape

Usability Testing

• What makes a good facilitator?– Clear understanding of goals– Good listening skills– Impartial – not wedded to a particular design – Quick thinking– Flexible and adaptable– Put people at ease & get them to open up– Able to ‘walk in shoes’ of others– What else?

Usability Testing

• Collecting data– Performance (Objective)

• Usually Quantitative– Time to complete a task– Time to recover from an error– Number of errors– Percentage of tasks completed successfully– Number of clicks– Pathway information

– Preference (Subjective)• Usually Qualitative

– Preference of versions– Suggestions and comments– Ratings or rankings (can be quantitative)

Usability Testing

• Analyzing the data• Quantitative data

– Statistics (number of clicks, errors rate, time, etc.)– Look for trends

• Qualitative data– Attitude, comments

Usability Testing

• Prioritize findings– Usability goals met?

• Prioritize tasks that performed the worst according to goals• Prioritize findings by frequency / importance• Prioritize recommendations by feasibility

• Implement and retest!

Participants did not understand the

difference between “other” and “related”

Participants did not notice the instructions.

Participants did not understand how this

list box worked, because is it possible to select both benign and malignant tissue.

Participants thought the default number

was too large.

Other Evaluation Methods

• Card Sorting• Paper Prototyping• Heuristic Evaluations / Usability Reviews

Card Sorting

• What is it?– Explores how users group items– Helps to develop structures that are logical to users– Maximizes probability of users finding info– Identifies items that are hard to categorize– Identifies terms that are interpreted differently by different

types of users

Card Sorting

• How to do it?– Participants are given a set of cards, with one item per card– Participants sort cards (content items) into logical categories

and assign labels to categories – Participants may sort cards into pre-defined categories– Participants may be asked to rename the individuals cards

or think of synonyms

• Benefits/Disadvantages?– Helps to develop categories that are logical to users– Helps to identify the items that need to be renamed– Helps with terminology– Sometimes it is difficult to analyze, tools have limitations

Paper Prototyping• What is it?

– Low-tech method that allows you to test early, before design and development

– Paper drawings of pages • How to do it?

– Participants are shown the paper prototype and given scenarios

– Participants are asked to point to where they would click

• Benefits/Disadvantages?– Helps to find problems early– Low-cost, saves development time– Help determine affordance (does it look clickable)

Heuristic Evaluation

• What is it?– Expert review of web site based on established usability

guidelines

• How do you do it?– Conducted by usability expert (best to include multiple

reviewers)– Experts review site for compliance/noncompliance with

established principles

• Benefits/Disadvantages?– Provides a reference of issues to be tested– Subjective– Not always accurate, identifies false positives– Not real users

Research and Resources

• Usability.gov Web Site– Online resource for those involved in Web site design

• Research-Based Web Design/Usability Guidelines– Topics: Web site goals, alignment, headers, fonts/line

length, frames, graphics, scrolling, download times, accessibility, page size, controls…

– Format: Guideline, comments, strength of research, source, graphic examples (do this/don’t do that)

• U-Group– Provides tips, tools, and information about developing

useful, usable Web sites and other health information systems

ContactCommunication Technologies Branch (CTB)Office of Communications • National Cancer Institute

Cari A. Wolfson6116 Executive Blvd, Suite 3048ARockville, MD 20852 301/496-1308 • fax: 301/435-6069wolfsonc@nih.gov