Fishbone Diagram

Fishbone diagrams (also called Ishikawa diagrams or cause and effect) are diagrams created by Kaoru Ishikawa (1915 – 1989) that show the potential causes of a specific event (problem). Common uses of the Fishbone diagram are quality defect prevention to identify potential factors causing an overall effect. Each cause or reason for imperfection is a source of variation. Causes are usually grouped into major categories to identify and classify these sources of variation. The categories are known as the 6M’s: Man (People), Method, Machine, Measurement, Mother nature (the environment), Materials.

As a team we discuss the potential causes we had noted earlier and place them onto the relevant category on the diagram. For example – Poor training may go under ‘Man (People)’, no training documentation available may go under ‘Method’, as so on.

We can then review the fishbone diagram and highlight common causes, such as ‘Training’.

When all of the common causes have been agreed and highlighted, we can move onto the next stage of Problem Solving……………5 whys!