Where device complaint handling breaks down
Most device makers can log a complaint. The failures come later: in the assessment of whether it is reportable, in investigations that stop short, and in trending that never triggers action. Complaint handling was the second most cited device observation in FDA’s FY2025 data, with 211 citations (GMP Insiders), and “inadequate complaint handling” ranked third in early QMSR inspections in 2026 (RAPS).
Two 2026 warning letters show the pattern. In one, FDA found the firm “closed these complaints without investigation,” did not open CAPA for device malfunctions, and stated, “Your firm’s complaint trending process is inadequate”; for one reportable event, “no MDR was received by the FDA” (FDA, Beta Bionics). In another, “no CAPA was initiated as the complaints trend did not meet the escalation criteria,” and an MDR was filed “beyond the 30‐calendar day timeframe” (FDA, Zoll).
For the FDA and EU MDR requirements behind complaint handling, see Medical Device Complaint Handling: FDA Requirements, MDR Reportability and a 2026 Checklist.
The requirements under the QMSR
Since February 2, 2026, device complaint handling follows ISO 13485 clause 8.2.2, incorporated into the QMSR, plus FDA’s added record requirements. Section 820.35 states: “In addition to Clause 8.2.2 in ISO 13485, Complaint Handling, the manufacturer shall maintain records of the review, evaluation, and investigation for any complaints” (eCFR, 21 CFR 820.35). Records must include the device name, date received, any UDI or UPC, complainant details, “The nature and details of the complaint,” corrective action and any reply. If no investigation is performed, “the manufacturer shall maintain records documenting justification for not performing such investigation.” FDA also notes that “Clauses 8.2.2, 8.5.2, and 8.3.1 of ISO 13485 address investigations of complaints” (Federal Register).
Step 1: Complaint assessment
Assessment is the triage that decides what happens next. Every complaint needs documented answers to four questions:
| Question | Why it matters |
|---|---|
| Is it a complaint? | Under the ISO 13485 definition used by the QMSR, communications alleging deficiencies in identity, quality, durability, reliability, usability, safety or performance are complaints, even if informal |
| Is it reportable? | US MDR (30 calendar days or 5 work days) and EU vigilance (2, 10 or 15 days) clocks run from awareness (eCFR, 21 CFR 803) |
| Does it need investigation? | If not, the justification must be recorded |
| What is the risk? | Severity and potential patient impact set priority and depth |
Step 2: Complaint investigation
A good complaint investigation answers what happened, why and whether it could happen again:
- Gather facts: returned device, lot or serial number, UDI, use conditions, patient outcome.
- Evaluate the device: inspection, testing and failure analysis where the device is available.
- Review records: device history, manufacturing and service records for the affected lot.
- Check for similar events: search past complaints and MDRs for the same failure mode.
- Determine cause with evidence, or document why it cannot be determined.
- Decide on action: correction, CAPA, risk file update or field action.
- Close with a clear conclusion and reply to the complainant where appropriate.
Step 3: Complaint trending
Trending turns individual complaints into signals. Effective trending:
- Codes complaints consistently by product, failure mode, harm and root cause, so counts are comparable.
- Normalizes by volume, such as complaints per units sold or procedures performed, to avoid false comfort from rising sales.
- Uses defined statistical methods and thresholds, for example control charts or rate comparisons, set in advance.
- Reviews thresholds for sensitivity, because criteria that are never met, as in the Zoll letter, can hide real problems.
- Feeds CAPA, risk management and management review, and, for EU products, Article 88 trend reporting on statistically significant increases in non-serious incidents (MDR Article 88, via Advisera).
How complaint data connects to the rest of the QMS
| Output | Destination |
|---|---|
| Reportable event | MDR (21 CFR 803) and EU vigilance |
| Confirmed defect or recurring failure mode | CAPA |
| New hazard or changed probability | Risk management file |
| Trend or signal | Management review, PMS report or PSUR |
| Field action | Corrections and removals (21 CFR 806) and FSCA |
Complaint investigation and trending checklist
- Complaint procedure updated to QMSR and ISO 13485 clause references
- Every complaint has a documented reportability decision with awareness date
- Records contain all 820.35 required content, including UDI
- Justifications recorded when no investigation is performed
- Investigations include device evaluation and history record review where possible
- Similar-event searches performed and documented
- Coding taxonomy defined and applied consistently
- Trend methods, normalization and thresholds defined and periodically challenged
- Trend results reviewed in management review and linked to CAPA
- EU Article 88 trend reporting criteria defined for EU products
Review complaint files with cited evidence
Complaint files fail inspections on details: a missing UDI, an unexplained decision not to investigate, a reportability call with no rationale. AskDona reviews complaint records, investigation reports and trend procedures against 21 CFR 820.35, 803, ISO 13485 or your own procedure, flags gaps and cites the passage behind every finding. Your team makes every reportability decision.
Run a sample complaint file assessment on a batch of closed complaints. AskDona shows the evidence; your team decides.
FAQ
What is complaint assessment? The initial evaluation of a complaint to decide whether it is reportable, whether it needs investigation and how urgent it is.
Does every device complaint need an investigation? Not always, but if no investigation is done, the justification must be recorded (21 CFR 820.35).
What is complaint trending? Analyzing coded complaint data over time to detect increases or new patterns that need action.
How should complaint trends be measured? Normalize by volume, use predefined statistical methods and thresholds, and review results regularly.
How do complaints relate to MDRs? Complaints are a primary source of reportable events; reportability must be assessed for each one.
References
All pages opened and checked by October 13, 2026.
| Source | Type | Date | Used for |
|---|---|---|---|
| GMP Insiders: FY2025 observations | Trade analysis | Jan 5, 2026 | Citation counts |
| RAPS: Top QMSR observations | Professional body | May 14, 2026 | QMSR findings |
| FDA warning letter: Beta Bionics | Regulator | Jan 28, 2026 | Investigation, trending, MDR |
| FDA warning letter: Zoll | Regulator | Apr 30, 2026 | Escalation criteria |
| eCFR: 21 CFR 820.35 | Regulation | Current | Complaint records |
| Federal Register: QMSR final rule | Regulator | Feb 2, 2024 | ISO 13485 clauses |
| eCFR: 21 CFR 803 | Regulation | Current | MDR timelines |
| Advisera: MDR Article 88 | Regulation text reproduction | n.d. | EU trend reporting |