A cause-and-effect diagram organises possible causes around a defined problem or effect. Also called a fishbone or Ishikawa diagram, it helps teams investigate beyond symptoms.
How to use this tool
State the problem precisely
Write a precise problem at the head of the diagram.
Agree cause categories
Agree appropriate cause categories.
Add possible causes
Add possible causes to each branch.
Confirm the root causes
Gather evidence to confirm the likely root causes.
References & further reading
Ishikawa, K. (1985). What Is Total Quality Control? The Japanese Way. Prentice-Hall.