ISO 13485 · Medium · 12 min lesson
DHR audit practice - reviewing a batch record, reconciliation, planted errors, the traceability test and DHR versus DMR
ISO 13485:2016 clauses 4.2.3, 4.2.5, 7.5.1, 7.5.9, 7.6, 8.2.4 and 8.2.6; 21 CFR 820.35(c); ISO 19011 audit guidance
What you will learn
- Select DHR samples and review a batch record in a repeatable sequence, including reconciliation and date and signature logic.
- Find planted errors in a record and run a backward and forward traceability test with a time target.
- Tell the DHR from the medical device file (former DMR), and write a finding with requirement, evidence and grade.
Key takeaways
- Sample DHRs by risk and read them in a fixed sequence: header, materials, process, label, reconciliation, release, index.
- Reconciliation is arithmetic: started equals the sum of outcomes and released never exceeds passed (clause 7.5.1).
- Dates, signatures and cross references find most planted errors: sequence, self-verification, expired calibration, mismatched lots.
- Run backward and forward traceability tests with a clock (clause 7.5.9); retrieval speed is part of record control (clause 4.2.5).
- The medical device file (clause 4.2.3, former DMR) says how; the DHR (clause 7.5.1) shows what was done; findings state requirement, evidence and grade.
Free practice question
An internal auditor asks Corvane for the record of lot 2440 chosen from the shipping list. The release page shows 4,830 released. The reconciliation shows 4,800 passed.
What is the correct reading?
Released cannot exceed passed; the amounts required by clause 7.5.1 are inconsistent and need investigation.
Correct. Clause 7.5.1 requires the amounts manufactured and approved to be identified, and 4,830 exceeds 4,800.
The difference is probably samples, so it is acceptable.
Not quite. A guess is not evidence, and clause 7.5.1 requires the recorded amounts to be consistent.
The shipping list is always right and the record wrong.
Not quite. Neither source is assumed correct; clause 7.5.9 requires the discrepancy to be investigated with evidence.
No issue because the release is signed.
Not quite. A signature does not cure a numerical contradiction in the record required by clause 7.5.1.
Key terms
- planted error: A deliberate inconsistency placed in a practice record to train reviewers to find defects by cross-checking.
- backward trace: A traceability test from a finished device back to its materials, processes and suppliers (clause 7.5.9).
- forward trace: A traceability test from a material lot forward to batches, shipments and consignees (clause 7.5.9).
- mock recall: A timed exercise that uses the records to locate all affected batches and consignees for a hypothetical defect.
- medical device file: The file of specifications and procedures for a device type (clause 4.2.3); it replaces the former device master record.
- internal audit: A planned, documented audit of the organisation by itself (clause 8.2.4).
- finding grade: Classification of a finding by effect on product and extent: observation, minor or major.
Official sources
- ISO 13485:2016 Medical devices - Quality management systems - Requirements for regulatory purposes
- 21 CFR 820.10 and 820.7, Quality Management System Regulation requirements and incorporation of ISO 13485 (eCFR)
- 21 CFR 820.35, Control of records (eCFR)
- 21 CFR 820.45, Device labeling and packaging controls (eCFR)
- 21 CFR 820.184, Device history record (former text, Cornell LII)
Go further
The full lesson has narrated slides, more scenario questions with explained answers and a simulation.
Open the AcademyWatch on YouTubeIllustrative example. Educational only, not legal advice.