Ishikawa Diagram
Overview
The Ishikawa diagram is also called the cause-effect diagram, the diagram fishbone or method of 5M.
What is Ishikawa diagram?
The diagram of Ichikawa is a graphical tool that takes the form of a fishbone. It allows you to view and analyze and the relationship between a problem (effect) and all its possible causes.
The use of the Ishikawa diagram has the following advantages:
- It allows to classify causes the problem.
- It helps to involve each team member for analysis.
- It allows to limit the causes of forgetfulness by the working group.
- It provides input for the study or solutions.
How to use the Ishikawa diagram?
The construction diagram of Ishikawa is based on group work. It is developed in several stages:
-
Clearly describe the problem.
-
By brainstorming, identify the main categories of causes. Often one uses a set of categories that we call the 5M: Manpower, Methods, Machines, Materials, Environment.
-
Draw the skeleton of the Ishikawa diagram and write categories.
-
For each category list the causes suggested by the group each time asking the question: why this book because it this?
-
Rank, if possible, the causes suggested sub-categories.
-
Determine the root causes that can be eliminated.
- Act on the cause to correct the deficiency by providing solutions and implementing corrective actions.
Example Ishikawa diagram
In a company of canned fish, the HACCP team has to do a hazard analysis.
For the stage setting, for example, the team used the diagram of Ishikawa to list all hazards that affect the safety of the product at that stage.
The diagram of Ishikawa established by the HACCP team is as follows:
