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Fishbone Analysis

Identify the root cause(s) of a problem statement.


What is a Fishbone Analysis?
Fishbone Analysis, a type of cause and effect diagram, can help in brainstorming possible causes of a problem and sorting ideas into useful categories. A key benefit of this analysis is pushing a team to consider all possible causes of a single problem, rather than the causes that are most obvious. This approach works on the principles that the true problem must be understood before action is taken.


How do I apply a Fishbone Analysis?
  1. Agree on a clear and specific problem statement (or effect). This is written at the mouth (right most blue box) of the “fish.” Avoid defining the problem in terms of a solution (e.g., we need more of something).
  2. Agree on the major categories of causes of the problem (outlined boxes).
  3. Brainstorm all the possible causes of the problem. Write the causal factor under the appropriate category (branch off central arrow).
  4. Continue to ask “Why does this happen?” about each cause and write sub-causes branching off the cause branches.
  5. Generate as many levels of causes as the team can identify and organize them under related causes/categories to identify the root causes of the identified problem statement.