1. Cause & Effect Diagrams
Scott Davis
QI Coordinator
Tacoma Pierce County Health Department
Recorded

2. Objectives Understand … Purpose of the CED Elements of the CED
How to construct a CED

3. CEDs When would I use this tool?
Most often: Late in the analysis phase when you want to develop theories of cause
You might also use it …
In assessment phase…to i.d. key drivers of an issue
Early in analysis phase…to organize stratification
In change phase…to consider solution options
Any time you consider how multiple factors might contribute to a specific phenomenon

4. Analysis Tool: Cause & Effect Diagram
“Fishbone” Format
(Aishikawa)

5. Effect Statement Examples
Outside referrals take more than a week to process. The data input step takes 3 to 5 hours. 34% of request forms are sent back. Why does printing permits take so long?

6. Analysis Tool: Cause & Effect Diagram
Typical Cause Categories
Machines
Methods (process)
Materials
Milieu (Environment)
Men (people)
Measurement
OR: Brainstorm causes on Post-It Notes and then group in natural affinities (see affinity diagram)

7. Analysis Tool: CED High-level Flow Format

8. Analysis Tool: “Why” Root Diagram Format
Cause Category
Cause Category
Effect Statement
As specific and measureable as possible
Specific Theory
Theory
Theory
Cause Category

9. Analysis Tool Centric CED Format
Cause Category
Theory
Cause Category
Specific
Theory
Effect Statement
Cause Category
Cause Category
Cause Category

10. Analysis Tool: Cause & Effect Diagram
Steps Write specific effect statement. (Usually, but not always, more specific than your original problem statement) Determine format Determine cause categories/steps Brainstorm theories of cause for each category Keep asking “why?” When complete, determine top 2-3 causes worth testing/investigating