How do you perform a root cause analysis using the Fishbone (Ishikawa) diagram?

How do you perform a root cause analysis using the Fishbone (Ishikawa) diagram?

• A. Identify problem effect and cause categories (man, method, material, machine, environment, measurement); brainstorm possible causes and test with evidence.
• B. List all possible hazards and assign random causes.
• C. Use a flowchart to document steps of an incident only after investigations.
• D. Focus only on human error as the cause.

Answer: (A)

The method tests a structured, multi-factor approach to uncover root causes. You start by clearly defining the problem and then build the Ishikawa diagram, labeling major cause categories (commonly the six Ms: man, method, material, machine, environment, measurement). From there, you brainstorm potential causes within each category, aiming for a wide, evidence-based list rather than jumping to a single attribution. After gathering data and testing whether each suspected cause actually contributed to the problem, you identify which factors are root causes that, if addressed, would prevent recurrence. This approach keeps thinking broad and systematic, avoids assuming one culprit, and ties findings to verifiable evidence. Other approaches fall short because they either resort to random or vague causes without structure, focus only on documenting steps after the fact, or zero in on one factor like human error and ignore other contributing elements.

The method tests a structured, multi-factor approach to uncover root causes. You start by clearly defining the problem and then build the Ishikawa diagram, labeling major cause categories (commonly the six Ms: man, method, material, machine, environment, measurement). From there, you brainstorm potential causes within each category, aiming for a wide, evidence-based list rather than jumping to a single attribution. After gathering data and testing whether each suspected cause actually contributed to the problem, you identify which factors are root causes that, if addressed, would prevent recurrence. This approach keeps thinking broad and systematic, avoids assuming one culprit, and ties findings to verifiable evidence.

Other approaches fall short because they either resort to random or vague causes without structure, focus only on documenting steps after the fact, or zero in on one factor like human error and ignore other contributing elements.