Medical device suppliers often get two requests for the same problem: the customer wants an 8D, and their own quality system wants a CAPA record. They don’t compete. In most ISO 13485 systems, CAPA is the process that decides whether action is needed, how far it goes and how it is recorded, and 8D is one structured way to do the problem-solving work inside it. This guide shows how the two fit together. It is general guidance, not regulatory advice; your own procedures, your customer’s supplier manual and any applicable regulations decide what is actually required.
Where the 8D sits in a CAPA process
A practical way to map them: the CAPA record holds the trigger, the risk decision, the plan, the approvals and the effectiveness review. The 8D holds the team, the problem description, the containment, the root cause and the actions. Many suppliers attach the 8D to the CAPA record, or reference the CAPA number in the 8D header, so an auditor can follow one trail.
- D1–D2: team and problem description, often reused from the complaint or nonconformance record.
- D3: containment and correction, linked to how nonconforming product is controlled.
- D4–D5: cause determination and action planning, the core of a corrective action.
- D6: implementation plus documented review of effectiveness.
- D7: read-across to similar products and processes, which is where preventive action thinking fits naturally.
- D8: closure, with the CAPA record closed under your own procedure.
For the wider comparison, see CAPA vs 8D.
Link it to complaint handling
ISO 13485:2016 has a documented complaint handling requirement (clause 8.2.2) that includes deciding whether a correction or corrective action is needed. When the 8D starts from a customer complaint, say so and keep the link visible:
- The complaint or notification reference, and the date it was received.
- Whether the complaint was investigated, and the reason if it was not.
- Whether your team considered the need to report to a regulatory authority. Who decides this, and how, comes from your own procedure and the customer, not from the 8D template.
- What happened to the affected product, including returned parts.
Keep CAPA risk-based
ISO 13485 asks for corrective and preventive actions that are proportionate to the effects of the problem. In practice, reviewers want to see why the depth of the 8D matches the risk. A cosmetic mark on outer packaging and a dimensional defect on an implant component should not get the same response.
- State the possible effect on device safety and performance, in plain words.
- Reference the product risk file or risk analysis if the failure mode is already in it, and say whether it needs updating.
- Explain why the chosen actions are enough for that risk, and what you chose not to do.
Check whether your 8D tells a clear story before it goes into the CAPA record or to the customer. Get a free Accept / Conditional / Reject advisory with missing evidence and questions.
8D Gate is a free pre-send readiness advisory. It doesn't replace the customer's decision. We don't store your 8D body in our database; you can delete anytime. Anthropic processes the text for the review.
Document verification of effectiveness
Under clause 8.5.2, a corrective action procedure covers verifying that the action does not adversely affect regulatory requirements or device safety and performance, and reviewing its effectiveness. In 8D terms that means D6 needs two different pieces of evidence:
- Did it work? Data over a defined period or number of lots, showing the failure mode no longer occurs or escapes.
- Did it break anything? A check that the change did not affect other requirements, for example a validated process, a test method or labelling. If a change touches a validated process, say how revalidation was assessed.
- Who reviewed the effectiveness evidence, when, and what the acceptance criterion was.
More on this in D6 verification of effectiveness.
Don’t drop preventive action
ISO 9001:2015 moved away from a separate preventive action clause, but ISO 13485:2016 still has one (clause 8.5.3): action on the causes of potential nonconformities. Some suppliers with an automotive or ISO 9001 background leave this out of their medical 8Ds. A short preventive section helps: which similar products, lines, sites or suppliers could have the same weakness, what you checked, and what you changed. D7 is a natural place for it; see D7: prevent recurrence.
Illustrative examples
These examples are fictional and only show the structure.
- Moulded housing, short shots: complaint reference in D2, risk note that the housing is non-patient-contact, cause verified by process data, effectiveness checked over the next lots, read-across to two other cavities and tools.
- Sterile barrier pouch, seal width: higher-risk failure mode, risk file reviewed, change to sealing parameters assessed against the existing validation, and the customer informed before shipping changed product.
- Machined component, burr: occurrence and escape causes separated, inspection method changed, and the same check applied to similar part families as preventive action.
Common weak spots
- The 8D and the CAPA record tell different stories or use different dates.
- No risk statement, so the depth of the response cannot be judged.
- D6 says “effective” with no data, period or acceptance criterion.
- No assessment of impact on validated processes after a change.
- No preventive or read-across section at all.
- Wording that suggests regulatory decisions were made by the supplier on the customer’s behalf.
For root cause quality, see how to write a D4 root cause. The free printable 8D / D4 checklist (PDF) covers D1–D8.
FAQ
- Does ISO 13485 require an 8D?
- No. ISO 13485 describes what a corrective and preventive action process must cover, not a specific report format. Many suppliers use an 8D because their customer asks for it, and link it to their CAPA record.
- Is this regulatory advice?
- No. This page is general guidance on structuring an 8D. Your own procedures, your customer’s requirements and the applicable regulations decide what you must do and report.
- What does 8D Gate check?
- It gives a pre-send readiness check on the 8D text: an Accept / Conditional / Reject advisory with missing evidence and questions. It isn’t a customer decision. The review tool is v0.1: it reviews English 8D reports, and the interface and report are in English. Templates are also available in German, Czech and Polish.
Free pre-send readiness check
Before the 8D goes out, run the text through the free supplier 8D readiness check.
Upload a PDF, Word (DOCX) or Excel 8D. You get an Accept / Conditional / Reject advisory, a score, section ratings, missing evidence, and questions to close gaps, with a PDF download. It is a pre-send readiness check for your team, not a customer decision.
8D Gate is a free pre-send readiness advisory. It doesn't replace the customer's decision. We don't store your 8D body in our database; you can delete anytime. Anthropic processes the text for the review.
Get the free 8D / D4 checklist
Keep the one-page version ready for the next complaint. It covers D1–D8 and goes deeper on containment, D4 root cause, and verification.
Get the free 8D / D4 checklist