Fishbone analysis visually displays the potential causes of a specific problem or effect under categories or sub-headings in a diagram in order to identify its root causes.
There may be many different opinions as to the root cause of a problem; fishbone analysis draws all these opinions together and displays them in an easily comprehendible way. As the potential causes or issues behind the problem are more thoroughly explored and understood, a more robust and sustainable solution may be found.
Fishbone analysis is particularly useful in a group setting and for situations where not a lot of quantitative data is available for analysis. This tool is often used together with Brainstorming and the ‘5 Whys’.
- To construct a fishbone diagram, start with stating the problem in the form of a question. For example: “Why do customer services receive a high number of complaints?”
- Doing this will help the team with the brainstorming as each cause idea should be an answer to the question
- The team should agree on the statement of the problem then put the agreed question in the box at the ‘head’ of the diagram
- The rest of the diagram consists of a vertical line from the head drawn across the page. Coming out diagonally from this line should be several lines, or ‘bones’. These ‘bones’ are labelled with different categories. The categories are up to you to decide, they depend on the project and subject matter under examination
- Once you have labelled the main category ‘bones’, start brainstorming possible causes and write them on the applicable ‘bones’
- For each of the causes identified, continue to ask ‘why does that happen?’ and attach that answer as another ‘bone’ of the main category ‘bone’
- Once the diagram is complete you will be well on your way to discovering the root causes of your problem. It would then be advisable to have the team prioritise the main causes identified on the diagram