The cause and effect diagram, Ishikawa diagram, fishbone diagram or 5M is a tool that was developed by Kaoru Ishikawa in the 1960s.
This tool can be used in different ways and is very useful.
I have often used it to solve complex problems. It helps to identify the potential causes of the problem or the causes leading to an effect (hence the name).
In a problem-solving context, once the potential causes have been identified, then the causes that need further analysis will be identified to find the root cause (s) of the problem. Then we need to find solutions to the causes of our problems.
It can help structure a brainstorming. Moreover, it is always better to do an exercise using a cause-and-effect diagram with a multidisciplinary team. The goal is to see the problem from different angles and experiences to identify the best possible causes for our problem.
It can also be used to understand or optimize a process and identify what causes a problem in the process, such as cost increase.
If you use it in a process optimization context, then you need to identify what can be improved.
As for the 5M name, it represents categories of causes to help you do your analysis. The categories shown below are often used, however, depending on your problem, you can put the categories you want, and you do not have to limit yourself to 5. You need to put the number that is needed according to your problem. For example, instead of putting the “means”, you can put the “equipment” if your problem is related to a manufacturing process. However, if you do not know which categories to use, the 5Ms are a good start.
It’s an easy-to-use tool that can help you a lot. Do not hesitate to use it! If you need help, contact us.