The Ishikawa Diagram (also Fishbone Diagram or Cause-and-Effect Diagram) is a structured way to brainstorm potential causes. The effect is the “Head of the fish” while the “Bones” and “Sub-Bones” contain the potential causes.
Typical categories for the potential causes (“Bones”) are:
- Mother Nature (Environment)
- Manpower (Personnel)
– Start from the head of the fish (= problem = deviation) and continue working to the fish’s tail
– Start on a high level, then brainstorm to a deeper, more detailed level
– Collect potential causes without prejudice
– It is not pivotal in which category a «thought» is put. The categories are mainly meant to ensure that potential causes are not overlooked