10. Toyoda’s (1958) Why-Tree for Root Cause
Analysis
Presenting
Problem
1st Main Reason 2nd Main
Reason
Why?
Why?
More
reason
s
More
reason
s
More
reason
s
More
reason
s
Why?
Root
Cause
Another
Reason
Another
Reason
Another
Reason
Another
Reason
Why?
Why?
12. Summary
Today we learned about different root cause job
aids: Six-box model, Fishbone diagram, and the
Why-Tree. Three important ideas to take away
are:
Expert analysts form mental maps of the
presenting problem(s),
Dig deep for the root cause to avoid
superficial-level interventions, and
Root causes are fundamental breakdowns or
triggers.
13. References
Binder, C. (1998). The six boxes-A descendant
of Gilbert’s Behavior Engineering Model.
Retrieved from http://www.binder-
riha.com/sixboxes.html
Dunn, E. J. & Renner, C. Root cause analysis:
Faculty development [PowerPoint]. VA National
Center for Patient Safety. Retrieved from
www.med.cornell.edu
14. Reference Continued
Ertmer, P. A., Stepich, D. A., York, C. S.,
Stickman, A., Wu, X., Zurek, S., & Goktas, Y.
(2008). How instructional design experts use
knowledge and experience to solve ill-structured
problems. Performance Improvement Quarterly,
21(1), 91-95. doi:10.1002/piq.20013
Willmore, J. (2004). Performance basics.
Baltimore, MD: ASTD Press.
Problems are like puzzles to me; a cognitive challenge to make things right. Today I’d like for us to discuss the tools and processes we use to solve problems. The learning objective for today’s training is to learn about 3 job aids that will help you form a mental map and uncover the root cause of a problem. The secondary learning objective is to learn to solve problem like an expert analyst. The purpose of problem analysis is to invite criticism, find faults, discover solutions, and therefore make performance improvements.
First, I’ll define some terms. Then, we’ll look at how an expert solves a problem. Before I continue, I’d like to activate your frame of reference and experience on this topic. Are you familiar with any of these 3 job aids? If so, which one have you found to be most effective? Do you use a different cause and effect model or job aid? If so, is it effective? Have you shared it with others on the job?
I selected this image because it demonstrates both the positive and negative sides to the problem. The obvious problem is the boat is too small for his catch. Who can highlight the other issues in this situation? Who can articulate a problem statement for this situation? Is this a ill-structured problem or well-structured one? Who knows the difference between the two? ANSWER: Well-structured problems have easily identifiable solutions. Ill-structured problems require problem-anaylsis.
Here’s my definition of problem analysis. Problem analysis involves a myriad of critical thinking processes, prescriptive activities, and discoveries. Activities include conducting a front-end analysis by asking questions, listening, observing, and looking over documents.
Remember that problems can be positive, too, so we need to look for triggers that could superficially appear to be helpful like rewards, but in actuality cause problems with productivity. Therefore, it is important to look at all aspects of a presenting issues, not just the negative ones. Digging deep for the root cause of a problem forces the analyst to go beyond the surface issues and avoid preparing interventions for superficial issues.
Peggy Ertmer and her colleagues conducted a case study in 2008 to find out what expert analysts do cognitively when they conduct a problem analysis. The pyramid illustrates 5 critical thinking processes used by experts to synthesize a presenting problem. (Give quick review of each.) We’re going to focus on creating a mental map by using a job aid to find root causes.
Sanders & Thiagarajan’s six-box model has 6 categories of performance improvement areas. It was developed specifically for the American Society of Training and Development (Willmore). This job aid will help you categorize the presenting issues, so you can get to the root cause of the problem. You have a copy of the model in the handouts. We will have a follow-up activity on this model later, so we can learn more about it.
Another root cause analysis tool is Kaoru Ishikawa’s (1969) fishbone diagram. It’s called a fishbone because of its structure. The main bones illustrate categories of performance problems and the minor bones stemming from it identify possible root causes. It does not have a set of categories as the 6-box model. Thus, Willmore suggested using a combination of the fishbone with the 6-box model categories to identify the root cause. Again, this helps us form a mental map of the problem like expert analysts do. You have a copy of a simpler version in your handouts.
Sakichi Toyoda first used the Why-Tree with the Toyota Industries Company in 1958. It consists of five why-questions that represent deeper levels of understanding of the problem. For each answer, you ask why until you uncover the true root cause. Willmore (2008) stated that not all the Why-Tree branches would need to extend five levels, as the root causes may surface after two or three questions. Again, this is another way to create a mental map to see the deeper issues and avoid implementing interventions at the superficial level.
(PREP AHEAD of TIME) Take a look at Sanders & Thiagarajan’s Six-Box Model handout and slips of paper with performance problems. Today’s task will ask you to place the corresponding performance issues in the appropriate category. You will work on this together as a group to negotiate. Once you’re finished, I’ll share the answer key with you.