Cause and Effect Diagrams (also known as fishbone diagrams, Ishikawa diagrams, herringbone diagrams or Fishikawa) are for getting to the underlying causes of an effect you are seeing. They were named after Kaoru Ishikawa, a quality pioneer. They can be used to identify the issues causing a problem, or the components that you need to consider to have the result you want.
The different branches should show the main issues / focusses at play in the process. There are standard ones for some areas that can give you a headstart:
5 M’s (Manufacturing) – Manpower, Materials, Machines, Methods, Measurement
7 P’s (Marketing) – Product, Price, Place, Promotion, People, Process, Physical Evidence
5 S’s (Service) – Suppliers, Surroundings, Systems, Skills, Safety
5 W’s – Who, What, When, Where, Why
4 P‘s – Policies, Procedures, People, Plant
- Draw a line across your paper through the middle lengthways
- Write your ‘effect’ that you want to analyse in a box to the right of the line
- Draw a branch away from this for each key component
- Draw a sub-branch away from these branches for the sub-cause (cause of the cause)
- Keep adding branches until it stops adding information
An example for me analysing why I was late for work.