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Cause & Effect / Fishbone
Every possible cause on the table. Only the proven ones stay.
A fishbone gets every possible cause out of people’s heads and onto one page, across six categories, without anyone having to defend a position. Then the evidence decides which bones stay.
Six categories, every possible cause on a rib, one effect at the head.
Challenge each bone
One carton in twenty prints off-colour. Apply the evidence.
Tap a category to see the suggested causes, then apply the evidence to see which survive. Illustrative example.
8 suggested causes across 6 categories
Anilox roller worn
SUGGESTEDApply the evidence to test this cause.
Dryer temperature drifting
SUGGESTEDApply the evidence to test this cause.
Since the 1990s
30
years investigating
250+
investigations closed, incl. HiPOs
15
countries served
20+
countries of lead seminars
100+
nationalities trained
Why teams like it
It ends the argument between departments.
Production, quality and maintenance all put their ideas on the same page, without blame.
Each idea is then tested against evidence, so seniority does not decide the cause.
Ruled-out causes are recorded, so the same argument does not return next month.
Use it for
Quality and process problems with many possible causes
Customer complaints and 8D responses
Getting a cross-functional team aligned
On its own it cannot
Show the sequence of events
Prove a cause without data behind it
Method names are given for reference. Several are proprietary or trademarked; P3i selects the approach that suits each case and does not claim licensed certification in proprietary methods.
A quality problem with too many possible causes? A first call costs nothing, and we will tell you how to narrow it down.
The P3i approach
How we investigate with a cause-and-effect map. Fact-finding, not fault-finding.
Every P3i investigation is led by a senior investigator and supported by internationally qualified process specialists. You will not receive a list of people to blame, or a long list of generic actions. You will receive the facts, the proven causes, and a short plan that closes the gaps, in this case and across your system.
Independent
No products, repairs or contracts to sell you afterwards.
Senior-led
Thirty years of investigation, from the first call to the final briefing.
Beyond the event
Process specialists find the other cracks before they fail.
Ready to present
Written for boards, buyers, insurers and regulators.
How P3i does it for you
- 01
Frame the problem sharply
One effect, stated precisely.
- 02
Map every category
People, methods, machines, materials, environment, management.
- 03
Challenge each bone
With data, not seniority in the room.
- 04
Keep the ones that are proven
The rest are parked, not argued about.
- 05
Act on the real causes
Owned, dated, tested.
What you receive
Call us when
Free 30-minute case assessment.
Tell us what happened. In confidence, we will tell you what the investigation should cover, how long it will take and what to preserve today.
Questions
What quality heads ask about fishbones.
What are the six categories?
Commonly people, methods, machines, materials, measurement and environment. We adapt them to services, hospitals and offices where needed.
Is a fishbone enough on its own?
It is excellent for generating possible causes. Each one must then be tested with data, which is where most internal fishbones stop short.
Why do you cross out causes?
Because proving what did not cause the problem stops the same theory being raised again, and protects people from unfair blame.
Can we use it for an 8D?
Yes. It fits the root cause step of an 8D and most customer CAPA formats.
Every idea on the board. Only proven causes in the report.
