We have discussed 5 WHYs to identify root causes of a problem in our previous blog.
What is more fun than 5 WHYs? It is a visual representation of WHYs – Fishbone or Ishikawa diagram.
The outcome of this technique is a diagram that looks like a fishbone. It was created by Kaoru Ishikawa in 1960s to show causes of an event. Initially, fishbone diagrams were used as a quality control tool but can be used for root cause, bottleneck or process analysis.
How do you build a fishbone diagram?
1. Set up a group/team, use a pen and paper or a board and chalk to draw the diagram.
2. Discuss and define the problem to solve. Draw the “backbone of a fish” and write the problem.
3. Discuss how to categorize causes. You can pick one of the established approaches or come up with your own way.
McKinsey 7S Framework offers Strategy, Structure, Systems, Shared values, Skills, Style and Staff as categories.
4Ps of Marketing suggests Product, Place, Price, and Promotion.
Functional approach uses Machine (or Policies), Method (or Procedures), Materials, Measurement, People and Environment.
Draw bones coming out vertically from the backbone of the fish. Label each bone with a category.
4. Brainstorm causes for each category and draw shorter lines coming out of bones. Label lines with causes.
5. Break causes into sub-causes if they are too complex or crowded.
6. Complete your diagram, analyze it; turn it around, clean it and analyze it again.
Fishbone diagram is effective and visual. A group can engage in exploring reasons and brainstorming robust solutions successfully.
It is simple and inexpensive. It doesn’t require any tool. You can build a fishbone diagram with limited quantitative data available for analysis.
Here is the link to some fishbone diagram templates: http://www.isixsigma.com/
Let us know your experience with fishbone diagrams.