A cause-and-effect fishbone diagram
Using the technique:
- First, identify the problem and write it down on a piece of paper with an arrow underneath it. Think about the exact problem in detail. Where appropriate, identify who is involved, what the problem is, and when and where it occurs.
- Identify the major factors and draw four or more branches off the large arrow to represent the main categories of potential causes. Categories could be: 'equipment', 'environment', 'procedures', 'people'.
Make sure that the categories you use are relevant to your particular problem.
- Take each of the main categories and brainstorm possible causes of the problem.
- Explore each one to identify more specific 'causes of causes'.
- Continue branching off until every possible cause has been identified. Where a cause is complex, you might break it down into sub-causes. Show these as lines coming off each cause line.
- Analyse your diagram. By this stage you should have a diagram showing all the possible causes of your problem. Depending on the complexity and importance of the issue, you can now investigate the most likely causes further.