five whys root cause system effectiveness: a two factor

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Western Kentucky University TopSCHOLAR® Masters eses & Specialist Projects Graduate School Spring 2019 Five Whys Root Cause System Effectiveness: A Two Factor Quantitative Review Barbara A. Key Western Kentucky University, [email protected] Follow this and additional works at: hps://digitalcommons.wku.edu/theses Part of the Industrial Technology Commons is esis is brought to you for free and open access by TopSCHOLAR®. It has been accepted for inclusion in Masters eses & Specialist Projects by an authorized administrator of TopSCHOLAR®. For more information, please contact [email protected]. Recommended Citation Key, Barbara A., "Five Whys Root Cause System Effectiveness: A Two Factor Quantitative Review" (2019). Masters eses & Specialist Projects. Paper 3098. hps://digitalcommons.wku.edu/theses/3098

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Page 1: Five Whys Root Cause System Effectiveness: A Two Factor

Western Kentucky UniversityTopSCHOLAR®

Masters Theses & Specialist Projects Graduate School

Spring 2019

Five Whys Root Cause System Effectiveness: ATwo Factor Quantitative ReviewBarbara A. KeyWestern Kentucky University, [email protected]

Follow this and additional works at: https://digitalcommons.wku.edu/theses

Part of the Industrial Technology Commons

This Thesis is brought to you for free and open access by TopSCHOLAR®. It has been accepted for inclusion in Masters Theses & Specialist Projects byan authorized administrator of TopSCHOLAR®. For more information, please contact [email protected].

Recommended CitationKey, Barbara A., "Five Whys Root Cause System Effectiveness: A Two Factor Quantitative Review" (2019). Masters Theses & SpecialistProjects. Paper 3098.https://digitalcommons.wku.edu/theses/3098

Page 2: Five Whys Root Cause System Effectiveness: A Two Factor

FIVE WHYS ROOT CAUSE SYSTEM EFFECTIVENESS:

A TWO FACTOR QUANTITATIVE REVIEW

A Thesis

Presented to

The Faculty of the School of Engineering and Applied Sciences

Western Kentucky University

Bowling Green, Kentucky

In Partial Fulfillment

Of the Requirements for the Degree

Master of Science

By

Barbara Key

May 2019

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I dedicate this thesis to my mom and in memory of my dad, an exceptional problem

solver who fixed or re-engineered all things around our house. Appreciation goes to my

dear husband, Ron, who singlehandedly managed our household during my countless

hours of study and research. Thanks to Katie and Lacey, who did not openly say mom

was crazy to take on this endeavor. Above all, thanks to God for bringing me through all

the challenges of life so I can share his love and blessings.

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ACKNOWLEDGMENTS

I would like to thank Don Wilczewski for CAMP facilitator instruction and

permission to adapt the forms and concepts shared. I am indebted to Melvin Cooper for

his encouragement, patience, and support throughout this project. Special appreciation to

the host sites for making the study possible. I appreciate the time and support of Dr.

Reaka and the interest, and encouragement of Dr. Revels. Most importantly, I would like

to thank Dr. Doggett for his wisdom, encouragement, and responsiveness, from our first

conversation regarding admission through completion of my degree program.

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CONTENTS

Chapter 1 - Introduction ...................................................................................................... 1

Problem Statement ......................................................................................................... 4

Significance of the Research .......................................................................................... 5

Purpose of the Research ................................................................................................. 6

Research Questions ........................................................................................................ 7

Assumptions ................................................................................................................... 7

Limitations ..................................................................................................................... 8

Delimitations .................................................................................................................. 8

Definition of terms ......................................................................................................... 9

Chapter 2 - Review of Literature ...................................................................................... 11

5 Whys root cause analysis .......................................................................................... 12

RCA effectiveness ....................................................................................................... 14

RCA facilitation .......................................................................................................... 17

RCA action classification ............................................................................................ 19

Chapter 3 - Methodology ................................................................................................. 22

Population .................................................................................................................... 22

Variables ...................................................................................................................... 23

Tools ............................................................................................................................ 25

Procedure ..................................................................................................................... 26

Method of Analysis ...................................................................................................... 28

Threats to Validity - Internal ........................................................................................ 28

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Threats to Validity - External ...................................................................................... 30

Chapter 4 - Results ............................................................................................................ 31

Chapter 5 - Conclusion and reccomendations for further study ....................................... 37

Appendix A: Completed 5 Whys analysis example ......................................................... 40

Appendix B: Completed action classification matrix ....................................................... 41

Appendix C: Root cause analysis scoring criteria ............................................................ 42

Appendix D: Example problem scenario .......................................................................... 43

References ......................................................................................................................... 44

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LIST OF FIGURES

Figure 1. Two factor experiment for effect on an outcome ............................................... 5

Figure 2. 5 Whys cause chain example ........................................................................... 14

Figure 3. Pareto of variables ............................................................................................ 32

Figure 4. Residual plot ................................................................................................... 34

Figure 5. Main Effect plot ............................................................................................... 35

Figure 6. Normal plot of standardized effects ................................................................. 35

Figure 7. Matrix of action strength and quantity ............................................................. 36

Figure A1. Completed 5 Whys analysis example ............................................................. 40

Figure B1. Completed action classification matrix. ......................................................... 41

Figure C1. Root cause analysis scoring criteria ............................................................... 42 Figure D1. Example problem scenario ............................................................................. 43

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LIST OF TABLES

Table 1. Study factors and levels ..................................................................................... 27

Table 2. Study factor and level randomized design table ................................................ 27

Table 3. Cohen’s kappa percent ....................................................................................... 31

Table 4. Cohen’s kappa statistics table ............................................................................ 31

Table 5. Main effects table ............................................................................................... 33

Table 6. Goodness of fits ................................................................................................. 33

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FIVE WHY ROOT CAUSE SYSTEM EFFECTIVENESS:

A TWO FACTOR QUANTITATIVE REVIEW

Barbara Key May 2019 51 Pages

Directed by: Dr. Mark Doggett, Dr. Mark Revels, and Dr. Bryan Reaka

School of Engineering and Applied Sciences Western Kentucky University

Several tools exist for root cause analysis (RCA). Despite this however, many

practitioners are not obtaining the quality improvement desired. Those turning to

literature for guidance would find most of the information resides in case studies with

anecdotal outcomes. Since 5 Whys analysis has been one of the more pervasive tools in

use, this study sought to add to the root cause analysis body of knowledge by

investigating tool support factors. While studied in conjunction with 5 Whys, the support

variables lend themselves to other root cause analysis tools as well. The purpose of the

study was to utilize a 2 x 2 factorial design to determine the significance and effect on

RCA effectiveness, of using a 5 Whys trained facilitator and action level classification.

During the study, problem solving teams at service centers of a North American electric

repair company conducted analysis with or without a trained facilitator. Additionally,

corrective actions were or were not categorized by defined levels of ability to impact

defect prevention. The dependent variable of effectiveness was determined by scoring

from a weighted list of best practices for problem solving analysis. Analysis showed

trained facilitators had significant effect on problem solving solutions, while

classification had minimal effect. Additionally, several opportunities for further study

were identified.

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Chapter 1 - Introduction

American car manufacturer Ford Motor Company introduced the team problem

solving methodology known as 8D in 1987 (Ford Power Train Operations Quality

Council, 1989) and it became the standard tool utilized in the automotive industry. Root

cause of an event was determined through several tools, one of which was 5 Whys.

Years later, in 1996, the Joint Commission on Accreditation of Healthcare Organizations

encouraged hospitals to report sentinel events and mandated root cause analysis (RCA)

for these events, with 5 Whys as an available tool for problem solving (Percarpio, Watts,

& Weeks, 2008). Both problem solving methods delineate a process step intended to

develop actions that eliminate the root cause, the fundamental cause that when corrected

prevents recurrence of the adverse event. Yet after decades of root cause analysis,

American automobiles have only outperformed imports on quality twice in 30 years (J.

D. Powers, 2016) and medical errors, when compared with diseases causing deaths,

ranked third (Makery & Daniel, 2016). Clearly, the 5 Whys, root cause method that has

been in widespread use within these business sectors, and others, does not provide

expected organizational learning and has significant room for improvement.

Investigations have identified an assortment of variables impacting problem

solving effectiveness. Major considerations are the lack of expertise of investigators and

weak corrective actions. Possessing minimal tool training and experience, investigation

teams do not always identify the root cause. Subsequently, the resulting actions will do

little to prevent recurrence. Additionally, since weaker actions do not insure the chain of

events gets broken every time, repeat events, sometimes called leakers, occur.

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In developing an individual’s mastery of skills, programs often require “hands on”

practice and a practical exam which demonstrates successful mastery. Many problem

solving facilitators have had only a cursory exposure to the tool. Without developed

deductive thinking and group facilitation skills, an RCA leader will not have much

success in getting to the root cause or in guiding the team toward establishing good

mistake proof actions. While these factors have been identified in the literature, the

impact of each among the host of situational variables has not been studied. This leaves

one to question where to start when improving an organization’s problem solving effort.

One study improved corrective actions by providing a list of actions from which to

choose that were compiled from similar events. This method stems from artificial

intelligence programming and use occurs when scientific laws or principles cannot be

employed. Intermediate generalities translate most effectively (Smith, 1998). Higher

level and situation specific lessons do not transfer; therefore, employing this method

warrants caution. Some learning of the current situation will take place. However, a true

understanding of the specific process that generates the event will not transpire from case

comparison alone, thereby leaving potential for adverse event recurrence.

Researchers commonly turn to design of experiments to quantifiably determine

the effects of variables on an outcome. A factorial design provides ability to determine

the impact of each variable as well as interaction effect between variables. This study

examined the influence on RCA effectiveness due to facilitator training and corrective

action classification. The outcomes included:

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1) A confirmation of knowledge about facilitator training when applied to

problem solving processes;

2) Exploration of action classification to improve RCA effectiveness;

3) A call for further research on strength of corrective actions.

Problem Statement

Due to less than desired results emanating from decades of root cause tool use, the

literature indicates the need for improvement still exists. While substantial studies claim

positive improvements from root cause analysis, the majority consist of single method

case studies with anecdotal results. This leaves non-practitioners interested in improving

their outcomes, with little evidence on which to base a direction for change, thereby

increasing risk and diminishing interest. Also, practicing RCA facilitators have been

handicapped by the lack of quantitative information regarding best practices that

positively influence RCA effectiveness. RCA efforts require significant time and

resources (Andersen & Fagerhaug, 2006) in already challenged work schedules.

However, the livelihood of businesses and human beings hang in the balance from the

resulting efforts and subsequent effectiveness. This demands proven methods that

support problem solving frameworks, especially in root cause analysis and corrective

action selection stages. The intent would be to standardize best practices for an

organization’s RCA teams and management, thereby resulting in desired improvement.

As further detailed in the review of literature, historical studies of RCA outcomes

have described the influence of team dynamics, investigation length, and action

implementation on poor RCA effectiveness. However, only a fraction considered the

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effects of facilitator training. While some attention has been given to striving for strong

actions, measurement of impact on RCA effectiveness was not quantified. Additionally,

attempts have been made to improve RCA by selecting known solutions from other sites,

rather than evaluating the potential effect generated for the current adverse event process.

Exposure to a 5 Whys problem solving process, utilized by an aerospace entity with

favorable results, created interest in quantifying the effects of factors supporting RCA

effectiveness.

The primary purpose of this study was to identify the effect of two variables

experientially identified as having favorable impact on RCA effectiveness. The variables

studied were trained facilitator versus untrained facilitator, and strength classification of

corrective actions versus unclassified actions. The model presented in Figure 1 was used

as the overall framework guiding this study.

Figure 1. Experiment schematic, effects of two independent factors on a dependent

factor.

The methodology section, chapter three, provides detailed discussion of the experimental

runs and controls.

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Significance of the Research

While the literature indicates RCA effectiveness has been reviewed across many

business sectors, using many tools, minimal research has focused on quantitative results

of effectiveness. Additionally, perhaps due to disappointing outcomes, much of the

literature seeks to add new tools. While a single tool has not gained prominence for its

results, a large number of case studies relied on the cause and effect diagram and 5 Whys,

sometimes using both to determine root cause. The 5 Whys tool provided an easy to

understand, easy to implement, and therefore less time consuming tool for determining

root cause, which no doubt contributed to the resulting popularity across business sectors.

Also, an organization desiring better results, would be more inclined to add proven

support elements to existing 5 Whys methodology rather than change to a more time

consuming or harder to use tool. Therefore, this study chose to focus on the 5 Whys tool.

The study aimed to provide root-cause tool users with two objectively validated

improvement elements, facilitator training and action classification. Additionally, the

quantitative nature provided a level of confidence for practitioners and through direct

correlation with the popular 5 Whys methodology, the study was applicable to a wide

audience. The study factors were additive to the problem solving process and therefore

have added potential to be transferrable to other root cause analysis tools.

Purpose of the Research

The purpose of this study was to leverage the power of design of experiment to

examine the effect of facilitator training and action classification on RCA effectiveness.

A two-by-two full factorial design was utilized. The trials and resulting analysis

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provided effect and significance of the independent factors of facilitator training and

action hierarchy on the dependent variable of RCA effectiveness. The researcher sought

to identify for practitioners support factors with obvious usefulness and value through

statistical confidence in the resultant outcome.

The expectation was effectiveness, measured through a scoring tool, increased

based on RCA facilitation by a trained individual and by assessing the prevention

strength of the planned corrective actions. Provided this was true, practitioners could

realize improvement by similarly implementing these factors.

The experiment involved an electrical component repair company with 12 service

centers throughout North America. These sites all serviced similar product and operated

under one quality system. The study was limited to four randomly selected service

centers. The variables of facilitator training and action classification were set at one of

two levels, “on” or “off”. Regarding facilitation, “on” meant a trained facilitator led the

RCA team, while “off” meant a team member with no special training led the group.

When action classification was “on”, the team used a classification matrix to determine

the strength of their solutions. No rating of solutions took place when the variable was

“off”. The settings were randomized per standard experiment test protocol or Yates

standard order (Barker, 1994) and analyzed for effectiveness based on a scoring tool of

RCA good practice.

Research Questions

1. Does use of a trained facilitator positively affect RCA effectiveness?

2. Does use of action classification positively affect RCA effectiveness?

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Assumptions

The following assumptions were made in the conduct of this study.

1. The random sample of incidents used for the company baseline and kappa

analysis was representative of the larger population.

2. The conducted experiment followed defined methodology.

3. The RCA scoring tool provided a valid representation of the root cause analysis

performed.

4. The selection process for teams and facilitators performing the analysis remained

constant throughout the study.

5. The facilitators conducted analysis teams with integrity

6. The action hierarchy tool provided a fair classification for corrective actions.

7. The study provided value for RCA analysis practitioners.

Limitations

The following limitations were identified for this study.

1. Work schedules facilitate attendance in analysis sessions for all required runs.

2. Outcome templates adequately represent the analysis for data integrity.

3. The RCA teams willingly and actively participated in the study.

Delimitations

The scope of this study has been defined by the following:

1. The design of the study was a two-by-two factorial experiment

2. Effects of all other RCA analysis support variables that may be in the study

system were not measured.

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3. The study was limited to use of the 5 Whys root cause tool.

4. The study was limited to the facilities of one electrical sector repair service

provider headquartered in upstate South Carolina.

5. Many variables identified in the literature affect RCA effectiveness; the study was

limited to facilitator training and action classification.

Definition of Terms

The following definitions are provided to clarify the terms used in the study.

8D: Framework of eight disciplines for team oriented problem solving. The

disciplines include: form the team, define the problem, containment actions, root cause

analysis, permanent corrective action, implement and validate actions, prevent

recurrence, and recognize the team. Utilization of a standard form serves to report and

archive the results of each step (Ford Power Train Operations Quality Council, 1989).

Action classification: A three tiered classification of cause mitigation actions.

The strongest actions are physical changes to the environment or process that aim to

remove the human element. Intermediate actions reduce similar language and

distractions. Weak actions raise awareness through training, warnings and additional

checks (Okes, 2009).

Corrective action: A solution meant to reduce or eliminate an identified problem

(ASQ, 2018).

Effectiveness: A measure of the appropriateness of the goals chosen and the

degree to which they are achieved (ASQ, 2018).

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Error-proofing, mistake proofing, or its Japanese equivalent poka-yoke: The use

of any automatic device or method that either makes it impossible for an error to occur or

makes the error immediately obvious once it has occurred (ASQ, 2018).

Facilitator: A skilled individual who enables a group to work through the problem

solving process to resolution by keeping the group focused and fostering productive

interaction between team members (VanGundy, 1992).

Natural team: A team of individuals with common or similar responsibilities and

authorities drawn from a single workgroup (ASQ, 2018). For example, a production

process natural team may include operators of process steps, inspection associate,

workflow specialist, material planner and engineer. For a medical surgical event, the

natural team may include the head nurse, the assisting nurse, the surgeon and the

anesthesiologist.

Root cause analysis (RCA): A collective term that describes a wide range of

approaches, tools, and techniques used to uncover the causes of problems (ASQ, 2018).

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Chapter 2 - Review of Literature

Root cause analysis can refer to a single tool or a system of tools used to

determine the cause of an event. No commonly accepted definition for root cause analysis

was found; but it has been suggested to be a process to identify causal factors causing a

gap in performance (Andersen & Fagerhaug, 2014). While the performance gap could be

positive or negative, RCA analysis most often occurs in literature in relation to adverse

events. The root cause analysis tools, of which there are many, have the objective of

assimilating and focusing team member’s process knowledge to discern root cause. In

this light, Mahto and Kumar (2008) provided an apt working definition for this study;

“Root cause analysis is a structured method to identify the causal factors contributing to a

problem with the intent of finding the root cause so that it can be resolved” (p. 16).

Problem solving processes vary in the number of steps required, but usually include:

understanding or defining the problem, identifying causes and potential solutions,

determining which actions to implement and validating solutions (Anderson &

Fagerhaug, 2006; Broome & Keever, 1989; Ford, 1989; Smith, G. F., 1998; Okes, 2009).

At least 39 problem-solving methods and 25 various cause identification tools have been

identified with a plethora of literature existing on how to use them. In the limited

comparison studies available, some tools have proven better than others. However, one

tool does not consistently distinguish itself as the best (Doggett, 2004; Sakar &

Mukhopadhyay, 2012; Smith, G. F., 1998; Yuniarto, 2012).

Consequently, while this study focused on the 5 Whys tool, any resultant positive

effects from the two factors studied, will likely translate to other problem solving tools.

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Due to this melting pot of methods, the literature review was not confined solely to

studies of 5 Whys tool use, rather an attempt was made to select from literature on RCA

analysis what was most pertinent to the goals of this study. The literature review has

been divided into the following main sections: 5 Whys root cause analysis, RCA

effectiveness, RCA facilitation and corrective actions.

5 Whys Root Cause Analysis

Generally done by a team involved in the work process, RCA analysis may have

roots in the Toyota Production System, as does 5 Whys analysis. The 5 Whys tool has

been attributed to Toyota pioneers from the fifties, such as Taiichi Ohno, who

encouraged managers to ask why five times for all problems encountered (Toyota, 2018).

The tool was not only used by managers. It was part of the total quality management

system, whereby employee teams were encouraged to solve work related issues (Smalley,

2018). This management theory was a synergistic result of seeds planted by Dr. Edward

Deming’s 14 points management philosophy. Deming encouraged management

involvement and all employees engaged in continuous improvement of the business

(Anderson, Rungtusanatham, & Schroeder, 1994). Some guidelines for root cause

analysis efforts identified in the literature (Andersen & Fagerhaug, 2006; Sakar &

Mukhopadhyay, 2012) included the following.

1) Utilize a team rather than an individual, preferably cross-functional

2) Team members are selected from the area impacted by the problem (generated

the issue)

3) Persons responsible for corrective actions are members of the analysis group.

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4) Analysis integrity depends on honesty and trust of team members to openly

share information without fear of negative consequences.

Anderson and Fagerhaug (2006) identified 5 Whys as one of four simplified RCA tools

along with Cause and Effects Diagram, Matrix Diagram and Fault Tree Analysis; the

remaining RCA tools were deemed “considerably more complex” (p. 117). This study

limited itself to the 5 Whys tool, for which Andersen and Fagerhaug (2014) provided two

versions. One version starts with the suspected root cause and works back to the event.

However, the method utilized in this study was the version in which the chain starts at the

top with the event posed in the form of a question. Subsequently, “Why?” repeatedly

asked and answered, until root cause was determined. The accepted norm of 5 iterations

of “Why?” provided the name for this tool. However, root cause may be determined with

fewer or more “whys”. The process requires proceeding until an answer can no longer be

provided. More precisely, stop when the action for the last answer will solve the problem

or the last answer falls out of the team’s sphere of influence or direct control (Jing, 2008;

Smith, J. L., 2017). As one moves down each why chain, the first answer after the event

question would be the direct cause, the last answer should be the root cause and the

answers in between are proximate or contributing causes. Contributing causes enable an

event, yet by themselves, do not cause the event. Therefore, actions taken on

contributing causes will eliminate symptoms, but will not stop the problem from being

created again (Barsalou, 2017). Figure 2 provides an example of a completed 5 Whys

cause chain.

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Figure 2. 5 Whys cause effect method. The chain flows down causes by answering each

why after the event question and flows back up by responding therefore after each effect.

Example adapted from Adams, T. (1861). The works of Thomas Adams: Being the sum

of his sermons, meditations, and other divine and moral discourses. Edinburgh: J.

Nichol.

The cause chain assessment used for the study, expected a cause chain for both

why the event occurred (why made), and for why the nonconformity, or adverse

condition, was not identified prior to customer impact (why missed). An example can be

found in Appendix A. An important learning comes from understanding that there are

usually multiple cause chains for any event being analyzed. The final why answer for

each chain, considered the root cause, becomes the target of subsequent action to prevent

recurrence. A basic understanding of the tool and the context of its use has been

presented. Next, the problems identified with 5 Whys and root cause tools in general will

be covered as part of a discussion on effectiveness.

RCA Effectiveness

RCA effectiveness depends upon identification of the actual root causes,

determination of corrective actions that prevent recurrence, and execution of those

actions. Lack of effectiveness emerged as a common theme in the literature regardless of

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root cause analysis tool utilized, with much of the current literature residing in studies

from the medical sector. In this sector, adverse events occur in 10% of acute admissions,

a rate that has not improved in 50 years, with serious events repeatedly recurring

(Braithwaite, Wears, & Hollnagel, 2014; Trbovich & Shojania, 2017). While the

problem-solving process has been successfully implemented in aerospace and other

safety sensitive industries, some suggest the tools are not adequate for or applicable to the

medical sector. The shortcomings identified were related to all three effectiveness

criteria. Reasons identified in the literature for lack of effectiveness were:

Weak or misapplied risk mitigation actions (Wu, Lipshutz & Pronovost,

2008; Trbovich & Shojania, 2017)

Poor implementations (Wu, Lipshutz & Pronovost, 2008; Vrklevski,

McKechnie & O’Connor, 2018)

RCAs performed incorrectly or incompletely (Wu, Lipshutz & Pronovost,

2008; Draper, 2015; Braithewaite, Wears, & Hollnagel, 2015; Trbovich &

Shojania, 2017)

Wide variance in quality of analysis (Wu, Lipshutz & Pronovost, 2008;

Trbovich & Shojania, 2017)

Repeat adverse events. (Wu, Lipshutz & Pronovost, 2008; Trbovich &

Shojania, 2017)

Team leader training and style (Yun, Sims, & Faraj, 2005; Trbovich &

Shojania, 2017)

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These items clearly indicate that the problem lies not as much in the problem-solving

process itself, but rather in consistently following the process.

Suggested solutions have included a database of perceived effective corrective

actions for teams to implement (Hettinger, Fairbanks, Hegde, Rackoff, Wreathall, Lewis

& Wears, 2013; Vacher, Mhamdi, d’Hollander, Izotte, Auroy, Michel & Quenon, 2017)

with the effectiveness of these actions determined by quantified perceptions or expert

validation. Literature has classified this as a systemic action and this path continues to

gain support despite mixed results. The concern becomes establishing tools based on

results the literature has identified as ineffective. While case-based problem solving can

be helpful, the solutions generated need careful consideration integrating into the process

under review. Problem solving processes in manufacturing usually include natural team

members and area support. For example, the relevant operators, engineer, and work flow

specialist, together provide the needed process expertise within that specific organization.

In the medical field, the participants in the adverse event are not usually on the

investigation team due to the human dynamics of guilt and blame that can impede causal

factor investigations of life threatening events. However, individuals from the event

facility, familiar with the particular process under review, are recommended (NPSF,

2016).

Subsequently, while these databases provide knowledge sharing and potential

brainstorming points, the corrective action needs to be tailored to the specific process

generating the event under review. Processes are comprised of manpower, methods,

machines, materials, measurements, and environment. These can be similar at a facility

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that delivers a baby in Boston and one that delivers a baby in California; however, the

sequence of steps and policies in place are not likely the same and the manpower and

environment differ. Galbraith (1977) noted that 75% of variables constituting any one

organizational setting are situationally specific; which further indicates the need to utilize

the expertise of individuals within the organization for problem solving events.

Therefore, while databases provide helpful information, this methodology supports a

greater danger of taking for granted the same solution will prevent recurrence in a

different setting.

A better approach utilizes the process experts at the event location and ensures

members exercise due diligence following and completing each step of the problem-

solving process. Items that cannot be prevented by actions within the team’s control,

such as equipment design changes, should be escalated to a governing authority for

investigation as a systemic issue for action. Two items that relate most to the

shortcomings delineated in the literature are RCA facilitation and adequate corrective

actions. Therefore, these will be explored in greater depth.

RCA Facilitation

Group problem solving has been part of human culture for a long time, especially

in government, and educational forums such as town halls and village schools. During

the early 1940s, studies began focusing on group interaction within organizations. This

spawned a field of study within social psychology intent on improving group

effectiveness (Keltner, 1989). Kurt Lewin’s work examining the superiority of group

decisions initiated use of work conferences with study groups rather than lecture. During

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one event, participants were able to further explore their own group dynamics with

observers, which led to establishment of the National Training Laboratory to further

study group facilitation. The work initiated by Lewin, Keltner, and other pioneers of

group training and facilitation, has provided a wealth of insight on the effect of

facilitation skills in helping groups be more efficient and effective (Bradford, 1974;

Broome & Keever, 1989; Keltner, 1989; Lewin, 1947). Lack of an appropriate RCA

framework and lack of strong leadership were identified as reasons teams quit analysis

prematurely and develop poor corrective actions (Percarpio et al., 2008). These

weaknesses combined with lack of implementation, contribute to all of the dissatisfaction

elements for effectiveness noted above.

This highlights the vital role of team facilitator and indicates their need for

problem solving process training in order to fulfill the obligation of insuring team actions

align with and fully complete the process. Conditions required for team success include

the right composition, a task that requires teamwork, effective use of resources, and a

supportive environment (Broome & Keever, 1989; Guzzo & Dickson, 1996).

Composition refers to adequate diversity among members, thereby avoiding group think.

Different perspectives contribute to consideration of a variety of potential causes and

solution alternatives.

Levi (2011) shared outcomes from several studies attempting to identify

characteristics of successful teams. Clear goals, appropriate leadership and

organizational support each were identified in three out of four major works (p. 29).

Appropriate leadership consists of managing relations, assisting with problems, and

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keeping the group on track. Teams that use shoot-from-the-hip problem solving or

implement previous solutions incur problems. Thus, structure and focus provided by a

facilitator not only minimizes these bad practices, it allows team members to feel

discussion time was useful and their goals were not jeopardized by another member’s

actions. These characteristics are important to member satisfaction and conflict

avoidance, becoming even more important as problem complexity increases (Antonioni

1996; Broome & Keever, 1989; Levi, 2011).

Rotondi (1999) further confirmed the importance of team engagement for creating

strong solutions with the results of his Team Problem Solving Assessment Tool (TPSAT)

for predicting likelihood of team success prior to committing resources. Lastly, use of

technology or group support systems (GSS), to assist in team facilitation has also been an

aspect of facilitation research. They have proven useful to teams for brainstorming,

categorizing information and communicating, but are not ready to replace human

facilitation (Bharat & Ross, 1998; Dennis & Wixom, 2002; Limayam, 2006). From social

psychology, one begins to see the importance of strong facilitation to ensure team success

in identifying root causes and viable counteractions. Due to the criticality of leadership

to team success, it was chosen as one of the variables to study.

RCA Action Classification

Once a team determines the root cause(s), the process requires determination of

solutions to mitigate those causes. For purposes of this study, the term corrective action

includes all actions taken; those to correct, to the extent possible, the specific

nonconformance that occurred; as well as, actions to improve detection, and actions to

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fail safe the root cause. When the cause applies to design or system issues, solutions may

require resources outside the team’s control using more involved techniques (Smalley,

2018; Smith, G. F., 1998). In this case, the team will have to address the causes

preceding the root cause and strive for the strongest solutions possible to reduce the

likelihood of recurrence.

Okes (2009) shared three categorization levels for solutions. The strongest

correction involves a physical change to the environment or process, such as mistake

proofing devices and controls, standardization of process steps, locations, and visual

indicators or elimination of the causal step. Intermediate solutions that reduce likelihood

of occurrence are achieved through job aids, separation of similar items, elimination of

distractions, checklists, read backs, and redundant actions. The weakest solutions involve

memos, warning labels, training and buddy checks. This classification, termed the

Action Hierarchy, was inspired by the safety sector (OSHA, 2018) and developed for

health care by the U.S. Department of Veterans Affairs in 2001 (Bagian, Gosbee, Lee,

Williams, McKnight, & Mannos, 2002; VA NCPS, 2009; NPSF, 2016; Hagley, Mills,

Shiner & Hemphill, 2018).

More recently, it has been included in the root cause analysis process strongly

recommended by the National Patient Safety Foundation (NPSF, 2016). The problem

solving methodology NPSF proposed was named RCA2, to emphasize the importance of

taking action after analysis. The guidelines were developed by a panel of subject matter

experts and stakeholders intent on improving the “inconsistent success” of root cause

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analysis effectiveness in healthcare. In fact, the RCA2 methodology has been endorsed

by 23 healthcare organizations (NPSF, 2016).

Consequently, this three level classification has depth of use, and stands on the

threshold of breadth of use. While working in the aerospace sector, the author also

observed that teams aware of the classification hierarchy generally work toward higher

level solutions than without such criteria. Due to The Action Hierarchy history in the

safety sector, additional adoption in government and aerospace sectors and recent added

endorsement for the medical sector, this factor was determined to be significant for the

study.

Appendices A and B provide an example 5 Whys and associated action

classification matrix. When a trial run of the design specified action classification, the

team used a blank action classification template, to determine the level of risk mitigation

provided by their solutions and to classify them as level one, two, or three. In this tool,

Level 1 represents strong solutions that knowingly break the chain of events, while level

2 involves intermediate solutions that reduce likelihood of occurrence, and Level 3

solutions provide limited effect, primarily through increased awareness.

As presented, the literature does not indicate a highly capable problem solving

process in widespread use and a single tool has not emerged as preferred for results and

ease of use. Previous studies indicated poor method results and called for additional

research in the body of knowledge related to problem solving tool effectiveness. These

studies also indicate the lack of leadership for teams to follow the process through to

completion and generate effective solutions. Therefore, the two factors of facilitator

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training and action classification were selected as variables having high potential for

favorable impact to the problem-solving process. Additionally, these factors can easily

be used to support any root cause analysis method and subsequently provide benefit

across a wide audience of problem-solving practitioners.

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Chapter 3 – Methodology

Population

The site population included twelve locations across North America. However,

one service center was utilized to prove out the training material and another for test case

development. Therefore, those two sites were excluded from the site population available

for the study. All service centers are one-shift operations, repair similar products, and

were presented the same problem set to analyze. An example can be found in Appendix

D. Company policy required associate problem solving for safety, production, and

customer issues; therefore, the process was not totally foreign and lack of participation

was not an obstacle. The workforce for all the North American plants has an average age

of 47 with a range of 20 to 77 with 9 percent of female gender. The study group

adequately reflected the company population. It included 8 percent females and an

average participant age of 46, with a range of 20 to 70 years old.

Random assignment, a precedent that precludes group effects confounding with

independent factors, was utilized to select team members. This departed from normal

assignment to the RCA team based on natural relationship to the adverse event.

However, it could be argued these teams fit the definition provide of a natural team for

two reasons. First, inherent to the nature of the service centers, most technicians had

expertise across multiple operations and the range of products serviced. Second, the

study problem assigned to the team was designed to be an event any of the sites could

potentially experience. Subsequently, the concern of a non-natural team lacking process

expertise needed for root cause determination was mitigated. The randomly selected

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teams came from all employees. Selectees were then randomly grouped into a team of

three, and a team of two to which the pre-trained facilitator was added. This made the

teams equal in all regards except for one having a facilitator trained in problem solving

using 5 Whys. Thus, internal and external validity was maintained. The company had

formalized event reporting, but had not yet conducted problem solving training.

Therefore employees had some familiarity with the problem solving process, with little

expertise. At one site; however, the recently hired site quality representative had

significant previous quality methods and problem solving experience. This threat to

result bias caused exclusion of that individual from the selection pool.

Effort was made to keep trial runs as close in time as possible. The first four trials

were made week one, the last four trials were made two weeks later. However, the

trained facilitator was not available for the last run so the two runs performed in

Pennsylvania had to be re-run at the alternate site in Alabama, two weeks later.

Therefore, all trials were run within a five-week time period. The study runs were

conducted as an opening exercise to company planned training for the site so there was

no collaboration or study anxiety among sites or participants.

Variables

Design of experiments is a structured, scientific methodology, and provides

statistical explanation for variation. The factorial design seeks to estimate and compare

the effects of the independent factors on the dependent variable, as well as estimate

possible interaction effects, and estimate precision (Juran, Gryna, & Bingham 1974;

Hildebrand & Ott, 1998). A full factorial experimental design was used to explore the

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effects of these two variables on root cause analysis outcome, as depicted in Figure 1

previously. The tool design facilitates one to “purposefully make changes to inputs (or

factors) to observe corresponding changes in the outputs (or responses)” (Kiemele,

Schmidt, & Berdine, 2000, p. 8-1). Many experiments study effects of two or more

factors. However, a factorial design proved most efficient since experimental error could

be determined as precisely as single factor experiments with less total observations

(Montgomery, 1984). Subsequent sections describe study construction and analysis.

One independent variable was facilitator training. When the run was coded

facilitator -1, the team used their existing problem solving practice, and recorded root

causes and corrective actions. Trained facilitators were used when the run was coded

facilitator +1. The facilitator was a person randomly selected from each of the four study

sites and the alternate site. These individuals attended three two-hour training modules

with two hours of problem practice, prior to leading a study team. All student facilitators

were trained by one trainer using virtual slide presentations with problem practice and

group discussion. The first training module covered the problem solving process and

using 5 Whys for root cause. The second module covered multiple leg 5 Whys, including

a leg for “why made” and a leg for “why missed”. This is shown in Appendix A. The

third module covered poka-yoke basics, and action classification. Attendance at all the

sessions was required and student facilitators presented an analyzed problem for feedback

from their peers and coach.

The second independent variable was action classification. When the test protocol

indicated this requirement via +1, the team determined the level of each of the actions

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developed to break each 5 Whys chain. These were recorded in the appropriate row of

the classification template. See Appendix B. The lowest level action, three, raises issue

awareness, but does not stop an event from occurring. Level two actions entail method

changes, but still depend on human compliance to be effective. One, the highest level,

identifies items that prevent the mistake or error from being created or forces

identification and action independent of human involvement. The level of each action

was determined by the scorers for teams that did not use the action classification

worksheet and action level was validated for teams that did use the action classification

sheet. The number of actions at each level contributed to the overall score the team

received for characteristic four on the scoring tool.

In this study, the dependent variable was 5 Whys analysis effectiveness as

measured by a scoring tool. The tool, found in Appendix C, consisted of a list of

characteristics identified as important to RCA team results. For the study, team size was

controlled at the smallest acceptable odd number so all teams received the same score for

category one.

Tools

Each team packet included a scenario with generic flow map, as shown in

Appendix D, and paper to record cause chains and actions. The scenario detailed

investigation information such as, where the problem originated and where it was

discovered, whether a procedure existed and was followed, as well as the quantity of

nonconforming units. Instructions were given to use problem solving methodology to

determine root cause and appropriate actions and to record the results on the blank sheets

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provided. Teams so designated were also given the classification tool and asked to

determine the level of each of their actions. The scoring tool was comprised of five

important characteristics related to a robust root cause analysis. It provided the empirical

outcome data for causes and actions produced from each run. Use of the tool generated a

score between 0-100 based on points attributed in each of the five desired categories.

The categories were 1) having a cross-functional team, 2) fully developed cause chain, 3)

completed containment, 4) high level corrective actions, and 5) systemic impact

consideration. The tool assigns higher weight to desired outcomes both within and

between characteristics. Therefore, the resulting score will not represent continuous

variables on the scale from 0-100.

Minitab was utilized to generate the run table for the design, the subsequent run

data analysis, and the scorers Kappa score. The kappa test, a widely used correlation

statistic, indicates reliability of measurements between raters (McHugh, 2012) and was

utilized in this study for scorer reliability utilizing the root cause effectiveness scoring

tool. Kappa scores can range from -1 to 1, with higher matching scores yielding a higher

kappa value. A negative score signifies less agreement than expected by chance, 0

expected by chance and perfect agreement equals one.

Procedure

Design of experiments are driven by the number of factors and levels evaluated,

as well as the type of data collected, but the process consistently involves: 1)

determination of the design and creation of a matrix of treatments, factors and levels, 2)

creation of randomized run plan, 3) collection of data, and 4) analysis of data. For

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quantitative factorial experiments, this includes sum of squares on responses, factor main

effects and interactions, significance of main effects and interactions based on level of

significance, and assessment of normality and residual values, or the difference between

observed and predicted values (Juran, Gryna, & Bingham 1974; Mathews 2005). This

study utilized a randomized two-by-two full factorial experiment, which consisted of two

factors at two levels as shown in Table 1.

Table 1

2x2 design of study factors and levels.

Action classification Facilitator Certification

Off On

No action classification

(off)

Facilitator trained, actions

not classified

Facilitator trained, actions

not classified

Action classification (on) Facilitator not trained,

actions classified

Facilitator not trained,

actions classified

The population could not be fully randomized due to multiple site locations being

many miles apart. Participants were randomly selected within a site and a randomized

replication was performed to mitigate potential group effects. The ten sites available for

study were assigned a number and five were selected by a random generator. The first

four numbers were the DOE sites and the fifth site was an alternate, should one be

required. The sites designated were Shreveport, LA, Houston, TX, Denver, CO,

Philadelphia, PA, and Dothan, AL as an alternate. The run list was generated in Minitab

as shown in Table 2.

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Table 2

Study randomized runs conducted at four sites.

Standard Order Run Order Site Facilitator Action levels

7 1 LA -1 +1

2 2 LA +1 -1

8 3 TX +1 +1

1 4 TX -1 -1

5 5 CO -1 -1

4 6 CO +1 +1

3 7 AL -1 +1

6 8 AL +1 -1

Note. Site column shows the site state. The facilitator at PA was absent, therefore run

conducted at AL, the backup site.

Utilization of a run procedure provided process consistency run-to-run:

1. Three individuals randomly selected from site population for non-facilitator RCA

team and two randomly selected individuals from the site population to team with

the trained facilitator.

2. Use of action level assigned to trained or untrained facilitator based on the

randomized run list in Table 2. Each group was given a run packet that included

the problem scenario, a generic process map, the action classification template, if

applicable, and a blank sheet of paper for recording 5 Whys, action and any other

results. The team had 45 minutes to determine causes, related actions, and record

results.

3. The run packets were returned to the scoring team and scored per the scoring

template.

4. The packets were collected by the researcher for data entry into Minitab.

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Method of Analysis

Minitab statistical software, a commercially available package, widely used in

many business sectors, was utilized for statistical analysis. Minitab version 17 generated

the run plan, analyzed the run data, and generated associated results graphs and tables.

Calculations included two-way analysis of variance of each independent variable based

on effectiveness score, graphs of main effects and interactions, and test for significance

of main effects and interactions.

Threats to Validity - Internal

Threats to external validity addressed in this section include history, maturation,

testing, instrumentation, statistical regression, selection, selection interaction and

experimental mortality (Grand Canyon University, 2018). The study could be subjected

to historical, maturation and selection threats. Participant interest in following through

with the study to completion could present both in lack of site management support and

individual interest, manifesting in lack of full employee engagement. Additionally, teams

at different locations create inability to fully randomize the company population.

However, random team assignment for each run at each site maintained equality among

teams and precluded selection effects.

Mortality affects and advanced preparation were precluded by randomly selecting

teams out of employees present on the day of the study, except for the pre-trained

facilitator. Since the duration of a single run was less than one day, it was anticipated the

team would stay intact for the duration of the run and therefore trial mortality effect had

low risk. The alternate site was trained in the event of facilitator loss during the study.

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The scoring tool, with accepted kappa, measured the results of all runs by two

scorers. Due to categorical weights, the scoring tool does not produce results in uniform

units across the scoring spectrum. However, it exhibited enough granularities to show

differentiation between desired and less preferred results. In relation to instrumentation,

all runs, at all locations employ the same procedure, problems, scorers and scoring tool.

Teams were not compensated for completing the analysis or for obtaining a certain score

to preclude rivalry and to maintain integrity.

The experiment time was compressed as much as possible to preclude albeit

unforeseen time based effects. The five-week span was the smallest permissible with the

reschedule of run four amongst other commitments. Additionally, sites were not aware

the runs were part of a study as they were conducted in conjunction with company

provided problem solving training. Therefore, maturation and selection effects were

deemed low risk as well.

Threats to Validity – External

The Hawthorne affect occurs when multiple treatments are applied to the same

group of subjects, causing a carryover into repeat runs that would not be evident from a

single time run. Potential existed for a treatment performed first with action level

classification or a trained facilitator to cause interaction effect or multiple treatment

interference on a subsequent run without action level classification or a trained facilitator.

Therefore, the study was randomly replicated and runs were performed on two randomly

selected teams at each site.

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Selection bias was low risk as teams consisted of random selection of technicians

available the day of the study. Effect due to differences in lab setting versus real world

was low risk because the runs occurred in the normal work setting, with problem sets

related to processes familiar to team members, and teams comprised of normal process

owners. It was expected that the workforce of this organization represents a typical

skilled trade organization in age, aptitude, gender, and learning skills. Utilizing true

work teams on a relatable process problem was considered the primary factor for

translatable results and thus gender effect was considered low risk for the independent

variables of this study. However, additional experiments of more diverse workforces

may be an area for further consideration.

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Chapter 4 - Results

The purpose of the study was to determine whether significant difference existed

in problem solving effectiveness among trained and untrained RCA facilitators and

classified and unclassified root cause actions. Effectiveness was measured through a

scoring tool validated using Cohen’s kappa for one trial with two appraisers. Prior to the

study, each rater was given the same set of 10 completed RCA analyses to score. The

scores were compared for agreement, with Table 3 and 4 representing the Minitab result.

Eighty percent matched with the kappa score itself close to the .7 minimum acceptance,

rather than the .9 preferred, Minitab guidance.

Table 3

Cohen’s kappa in percent between appraisers assessment agreement

# Inspected # Matched Percent 95 % CI

10 8 80.00 (44.39, 97.48)

Table 4

Cohen’s kappa statistics for between appraisers agreement

Response Kappa SE Kappa Z P(vs>0)

15 1.00000 0.316228 3.16228 0.0008

18 1.00000 0.316228 3.16228 0.0008

20 0.00000 0.000000 * *

25 1.00000 0.316228 3.16228 0.0008

30 0.52381 1.65643 1.65643 0.0488

33 1.00000 0.316228 3.16228 0.0008

35 1.00000 0.316228 3.16228 0.0008

40 0.00000 0.000000 * *

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Overall 0.75904 .132475 5.72964 0.0000

Each score was a summation of five category scores so effort was made to clarify point

levels within a category. A trial run scoring two analyses indicated some variation in one

category of the tool so the verbiage was refined for the cause chain characteristic. This

produced the kappa results given herein on a set of ten analyses that did not include the

two used in the initial proving run. Appendix D shows the final version of the scoring

tool.

The effectiveness score from each rater was averaged together and entered into

Minitab as one effectiveness score. A Pareto chart of variables and subsequent

interaction indicated that the trained facilitator had significant affect, see Figure 3.

AB

B

A

3.02.52.01.51.00.50.0

Te

rm

Standardized Effect

2.776

A Faciliatator

B A ction Lev els

Factor Name

Pareto Chart of the Standardized Effects(response is Eff Score, Alpha = 0.05)

Figure 3. Pareto chart showing variable and interaction effects.

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Additionally, the main effects data, Table 5, shows a P- value for facilitator below the

.050 alpha significance level, which also indicates that facilitator training has impact on

effectiveness score.

Table 5

Main effects of trained facilitator and action classification on effectiveness score.

Term Effect Coefficient SE

Coefficient

T P

Constant 50.625 3.094 16.36 0.000

Facilitator 17.50 8.750 3.094 2.83 0.047

Action Levels 6.250 3.125 3.094 1.01 0.370

Facilitator x Action Levels -2.500 -1.250 3.094 -0.40 0.707

In Table 6, the R-Sq indicated the experiment predicted 69.66% of the variation found. A

good predictor of future readings would have been evident with a low S value and a high

R-Sq (pred), which did not occur. This may be an indication that an unnecessary factor

was included, requiring review of the residuals. See Figure 4.

Table 6

Goodness of fits table

S Press R-Sq R-Sq (pred) R-Sq (adj)

8.75 1225 69.66% 0.00% 46.90%

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20100-10-20

99

90

50

10

1

Residual

Pe

rce

nt

6055504540

10

5

0

-5

-10

Fitted Value

Re

sid

ua

l10.07.55.02.50.0-2.5-5.0-7.5

2.0

1.5

1.0

0.5

0.0

Residual

Fre

qu

en

cy

87654321

10

5

0

-5

-10

Observation Order

Re

sid

ua

l

Normal Probability Plot Versus Fits

Histogram Versus Order

Residual Plots for Eff Score

Figure 4. Effectiveness scores residual plot.

The residual plot does not indicate unusual trends or outliers. The resulting conclusion

drawn was the scoring tool was not discrete enough to capture any changes produced

through use of the classification matrix. In fact, one facilitated team did not use the

matrix further reducing a somewhat small sample size. The main effects and normal

plots, Figure 5 and 6, show the positive impact of using a trained facilitator. The action

levels had a small, yet statistically insignificant positive effect.

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Figure 5. Interaction plots of trained facilitator and action classification.

3210-1-2-3

99

95

90

80

70

60

50

40

30

20

10

5

1

Standardized Effect

Pe

rce

nt

A Facilitator

B A ction Lev els

Factor Name

Not Significant

Significant

Effect Type

A

Normal Plot of the Standardized Effects(response is Eff Score, Alpha = 0.05)

Figure 6. Interaction plots of trained facilitator and action classification.

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The total quantity and number of stronger actions was greater among facilitated teams as

shown in Figure 7.

Figure 7. Matrix of action strength and quantity by team.

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Chapter 5 – Conclusion and Reccomendations for Further Study

Counter to the hypothesis, not all factors in the study proved significant.

However, significant learning occurred on the difficulty of quantifying subjective

elements and developing study scenarios. The key takeaways related to variables and

responses are as follows.

First, in any quantifiable endeavor, there should be an analysis of the

measurement system. The scoring tool was a consolidated assessment of five categories

into one score, which added complexity. While measurement system analysis was

completed in this study without negative impact, a more robust analysis replicating

appraiser scores and if possible, having a known standard, would provide greater

statistical insight and potential scoring tool improvement. The amount of time required

to translate solved issues into a useable case study for run scoring was underestimated,

yet proved fruitful. Teams worked the scenario based on the information provided and

scoring tool results indicated the effect of utilizing a trained facilitator was significant.

This was expected based on team performance studies from the literature; however, many

companies still fail to follow this protocol. This study reconfirms the importance of

trained facilitators in problem solving teams.

In the study, three of four facilitated teams had significantly higher scores than

un-facilitated teams. This effect, with the minimal training provided, provides an

indicator of the importance of training facilitators. Additionally, practitioners improve

proficiency and confidence with practice. An increased amount of practice time may

provide greater impact to the facilitation score. A corollary noticed, but not actively

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studied, was three of four facilitated teams focused quicker and reached consensus sooner

than all the non-facilitated teams. Subsequently, the improvement obtained for the small

training and practice time invested in this application indicates a significant return on

investment. In the work environment of today, which demands higher productivity in

ever shrinking elements of time, training becomes more essential and improves likelihood

of resolution on the first pass.

The factor of action level classification had no significance and slightly improved

effect with the trained facilitator. In this study, some impact may have been lost from a

facilitated team that failed to use the matrix and a non-facilitated team that was

apprehensive using the new tool. Additionally, the scoring tool, good for overall

appraisal of a problem solving effort, may not have been an adequate indicator to

establish effect by just one category. A more granular, continuous assessment tool may

be required. Finally, with definitely one run, and possible two of the eight runs using the

matrix compromised, the tool should be re-evaluated. Selection of action classification as

a study factor was predicated on prior experience with introduction of action

classification after trained facilitation was the standard. In that environment,

classification of actions yielded more error proofing and resulted in decreased parts per

million defective. For these reasons, this best practice warrants additional study before

dismissing its value. Particular interest would be the effect of the classification matrix

used with teams already experienced in problem solving, but not already utilizing a

similar tool.

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Several areas for future research were evident from the study. A larger sampling

for action classification, utilizing a more discrete tool was the primary one. 5 Whys is a

skill improved with practice. However, time for training can be hard to justify.

Therefore, an analysis to determine the range of time it takes students to attain 5 Whys

proficiency could be beneficial to the problem solving body of knowledge. Lastly,

research of more diversified populations and application to other problem solving tools

would add confirmation for widespread applicability of these two support practices.

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Appendix A: Example 5 Whys cause chain with why made and why missed

Figure A1. Example 5 Whys cause chain with why made chain and several why missed

chains.

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Appendix B: Completed action classification matrix

Figure B1. Mistake proof action classification template completed for 5 Whys in Figure

A1. Adapted with permission from Wilczewski, D., (2016).

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Appendix C: Root cause analysis and action scoring criteria

Characteristic Score Points Comments

1 Team

Activity

0 Problem owner only

3 At least two associates

5 3 or more team members, more than 1 functional

area

2 Cause Chain 0 Missing (if a cause is given, go to next level)

10 Missed listing all contributing causes or did not

complete for why made and why missed, or

missing root cause(s).

20 Cause chain but missing additional legs or

contributing causes to develop or doesn’t flow

forward and backward.

30 Event question aligns with the finding, fully

developed why made and why missed chains that

work forward and backward, root cause identified.

3 Containment

Actions

0 No containment listed and no justification why.

5 Containment noted but only covered the NC item

and/or lacks detail (how many NC/total in RECV,

WIP, Transit in or out, and Customer locations).

15 Containment actions detailed but not timely.

20 Process stop until containment completed. All

applicable containment areas addressed. All

activity documented and within required timeline.

4 Corrective

Actions

0 No or very weak CA. i.e. monitor process, first

failure, isolated incident - one off.

5 Only level 3 actions given.

15 One level 2 action, or primarily added inspection

or visual management.

25 Level 1 action or two level 2 actions

5 Systemic

Actions

0 No action taken or copied/repeated actions given

for corrective and preventive actions.

10 Other areas considered but actions not strong

enough to prevent occurrence in other areas.

20 Actions address contributing and root cause on

other potentially affected processes or reason

given why systemic action is not required.

Sum of points received for each of the 5 characteristics equals total effectiveness score.

Figure C1. Root cause analysis scoring criteria. Adapted from Wilczewski, D., (2016).

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Appendix D: Example problem scenario

Figure D1. Example problem scenario and generic process map.

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References

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meditations, and other divine and moral discourses. Edinburgh: J. Nichol.

American Society for Quality (2018). Quality glossary definition: Root cause. Learn

about quality. http://asq.org/learn-about-quality/root-cause-

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