Fishbone (Ishikawa) Worksheet — Example & Template

This worksheet helps you run a structured fishbone session and capture the most probable causes for later analysis.

How to use

1. Write the problem statement on the fishbone head (make it measurable).
2. Label major bones using categories that fit your context (e.g., People, Process, Equipment, Materials, Environment, Measurement).
3. Brainstorm causes and pin them to the relevant bone. Encourage evidence-based contributions ("I observed X" or "Log shows Y").
4. After brainstorming, vote or prioritize top cause lines to investigate with 5 Whys or data collection.

Blank template (copy into a board or whiteboard)

Problem statement: _______________________________

Categories: People | Process | Equipment | Materials | Environment | Measurement

Top candidate causes (short list):

1. ________________________________________
2. ________________________________________
3. ________________________________________

Example (composite)

Problem: High rate of returned widgets due to dimensional out-of-spec.

• People: New operators during night shift had abbreviated training (evidence: training logs).
• Process: Final inspection not sampling every batch (evidence: inspection checklist).
• Equipment: Cutting tool worn beyond spec (evidence: maintenance log shows overdue replacement).
• Materials: Supplier batch variance higher last month (evidence: supplier certificate of analysis).
• Measurement: Measurement gauge not calibrated this quarter (evidence: calibration records).

Top lines to investigate: Equipment wear, calibration, and inspection process.