- What is a Fishbone Diagram?
- A Fishbone diagram is a “Cause and Effect” diagram. The importance of the FBD is that is that it uses visual power to highlight the problems and relationship between problems and their potential sources.
- When to use a Fishbone Diagram?
- When a simple approach is needed to reduce the effect of a problem(s);
- When identifying possible causes for a problem;
- When problem solving has gone stale and the team needs a fresh approach.
This is a typical example of a FBD template. Generally there are 6 major branches (some header titles may be varied):
- Man or manpower (People)
- Method (Process)
- Mother Nature (Environment)
- Agree on a problem statement (effect) and write it at the end of the horizontal arrow.
- Brainstorm the causes that influence the effect – do this for all categories (branches).
- Arrange and strategize the causes. Decide on principle causes and show these as the major branches off the horizontal arrow.
- Create sub-branches for the causes. Continue to sub-divide all the causes for each branch until all causes are included.
- Review chart to ensure all known causes of variation are included.
Fishbone diagram completed
Once the Fishbone is created, the team should decide:
- Do we need to collect data at certain processes?
- Do we need to revisit any causes or factors for reconsideration?
- Make an action item list for all opportunities and follow through
Good to Great
When a process is predictable (in control), the Fishbone diagram will assist in identifying continuous improvement opportunities for a better process.
When a process is not predictable (out of control), the Fishbone can identify areas for continuous improvement by removing non value added activities to create a more stable process.