How to use Ishikawa methodology to perform a root cause analysis

The Ishikawa methodology uses an Ishikawa diagram as a graphical tool to help your team to brainstorm and identify the causes and the categories of causes that result in the problem. The categories help the team to ensure that all causes in a particular category are recorded. If a category has few causes, the team can focus their brainstorming on that category to capture any missing causes. If the team analyzes a cause and finds that it requires additional investigation, they can create child causes for that specific cause. After identifying all the causes and listing them in the correct categories, you can analyze the diagram to mark the root cause of the problem.

An Ishikawa diagram is also called a cause-and-effect diagram or a fishbone diagram because it represents the causes and their effect in the form of a fishbone.

You can organize the causes in groups depending on the requirements of your industry. You can use some of the following categories to group your causes:

• Man: In this category, you can list the causes related to the people involved in the problem.

• Machine: In this category, you can list the causes related to the equipment involved in the problem.

• Method: In this category, you can list the causes related to the methods and procedures involved in the problem.

• Material: In this category, you can list the causes related to the raw materials and parts involved in the problem.

• Measurement: In this category, you can list the causes resulting from measurement-related problems.

• Mother Earth: In this category, you can list the causes resulting from environment-related problems.

• Product: In this category, you can list the causes resulting from problems with the product.

• Price: In this category, you can list the causes resulting from problems with the price of the product.

• Promotions: In this category, you can list the causes resulting from problems with the promotions used for the product.

• Place: In this category, you can list the causes resulting from locations where the product is sold.