Cause & Effect/FishBone Diagram

Find & cure causes, NOT symptoms

Why use it?

To allow a team to identify, explore, and graphically display, in increasing detail, all of the possible causes related to a problem or condition to discover its root cause(s).

What does it do?

How do I do it?

  1. Select the most appropriate cause & effect format. There are two major formats:
  1. Generate the causes needed to build a Cause & Effect Diagram. Choose one method:
  1. Construct the Cause & Effect/Fishbone Diagram.

a) Place the problem statement in a box on the right-hand side of the writing surface.

Make sure everyone agrees on the problem statement. Include as much information as possible on the “what,” “where,” “when,” and “how much” of the problem. Use data to specify the problem.

b) Draw major cause categories or steps in the production or service process. Connect them to the “backbone” of the fishbone chart.

c) Place the brainstormed or data-based causes in the appropriate category.

If ideas are slow in coming, use the major cause categories as catalysts (e.g., “What in ‘materials’ is causing . . . ?”).

d) Ask repeatedly of each cause listed on the “bones,” either:

For each deeper cause, continue to push for deeper understanding, but know when to stop. A rule of thumb is to stop questioning when a cause is controlled by more than one level of management removed from the group. Otherwise, the process could become an exercise in frustration. Use common sense.

e) Interpret or test for root cause(s) by one or more of the following:


Traditionally, Cause & Effect Diagrams have been created in a meeting setting. The completed “fishbone” is often reviewed by others and/or confirmed with data collection. A very effective alternative is CEDAC®, in which a large, highly visible, blank fishbone chart is displayed prominently in a work area. Everyone posts both potential causes and solutions on sticky notes in each of the categories. Causes and solutions are reviewed, tested, and posted. This technique opens up the process to the knowledge and creativity of every person in the operation.

Cause & Effect/Fishbone
Bed Assignment Delay
Information provided courtesy of Rush-Presbyterian-St. Luke’s Medical Center
Cause & Effect/Fishbone
Causes for Bent Pins (Plug-In Side)
Information provided courtesy of AT&T
Cause & Effect/Fishbone
Damaged Door Panels
Information provided courtesy of Marvin Windows and Doors
Cause & Effect/Fishbone
Emergency Preparedness
Information provided courtesy of Cook Children’s Health Plan
Cause & Effect/Fishbone
Financial Institutions
Information provided courtesy of Province of Nova Scotia, Canada
Cause & Effect/Fishbone
Variance to Plan
Information provided courtesy of Nevada Power

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