These diagrams are also called as Cause and Effect diagrams or Fishbone diagrams as they resemble a Fishbone. These are also used in risk analysis.Here the causes are grouped into categories, this helps in identifying the root cause of the problem.

The categories may include:

People
Method
Machines
Materials
Measurements
Environment

For manufacturing industry- 8 Ms are used.
in Service industry – 8 Ps are used.

Note: A root cause can be uncovered by asking why or how continuously. This is a common technique.

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