Which of the following is listed as a root-cause identification method?

Which of the following is listed as a root-cause identification method?

• A. 5-Why's
• B. Fish-bone/Ishikawa
• C. Both of the above
• D. There are no such methods

Answer: (C)

Root-cause identification relies on techniques that help you trace problems back to their underlying cause rather than just addressing symptoms. Two widely used methods are 5-Why’s and the Fishbone (Ishikawa) diagram. 5-Why’s is a simple, iterative questioning approach: you ask “why?” about the problem, then again about the answer, and keep going until you reach a fundamental, underlying cause. It’s especially useful for quick, focused investigations or when you have limited data. The Fishbone diagram helps you visualize and organize potential causes across categories (such as people, processes, equipment, materials, environment, and management). By laying out possible contributing factors visually, it’s easier to see interrelationships and identify areas to investigate more deeply. Using both together is common: use the Fishbone to surface a broad set of potential root causes, then apply 5-Why’s to drill down into the most likely causes and verify the true root cause. Therefore, recognizing both methods as valid root-cause identification techniques aligns with best practices, while options suggesting that neither method exists are not correct.

Root-cause identification relies on techniques that help you trace problems back to their underlying cause rather than just addressing symptoms. Two widely used methods are 5-Why’s and the Fishbone (Ishikawa) diagram.

5-Why’s is a simple, iterative questioning approach: you ask “why?” about the problem, then again about the answer, and keep going until you reach a fundamental, underlying cause. It’s especially useful for quick, focused investigations or when you have limited data.

The Fishbone diagram helps you visualize and organize potential causes across categories (such as people, processes, equipment, materials, environment, and management). By laying out possible contributing factors visually, it’s easier to see interrelationships and identify areas to investigate more deeply.

Using both together is common: use the Fishbone to surface a broad set of potential root causes, then apply 5-Why’s to drill down into the most likely causes and verify the true root cause.

Therefore, recognizing both methods as valid root-cause identification techniques aligns with best practices, while options suggesting that neither method exists are not correct.