Fishbone (Ishikawa) Analysis

When to use

Use fishbone analysis to brainstorm all possible causes of a quality problem before running 5-Why. It prevents tunnel vision and ensures no cause category is overlooked. Particularly valuable for complex defects with multiple potential contributing factors.

Typical use: 8D D4 brainstorming session, CAPA root cause investigation, initial problem analysis.

Prerequisites

• Problem clearly defined with Is/Is-Not or 5W2H
• Cross-functional team (quality, production, engineering at minimum)
• Access to the process, machine, or product where defect occurred

Required Fishbone Checklist