Preparing a medical-device internal audit — trace one product across process boundaries

Check documented requirements and actual implementation separately

An approved procedure does not by itself demonstrate that people follow it. An internal audit moves between requirements and actual records. Do materials in a manufacturing record match approved purchasing specifications? Were the required inspections completed before release? Connections between activities are useful places to investigate.

Section 8.2.4 of Annex 2 to Korea’s medical-device manufacturing and quality management standard addresses audits at planned intervals, documented criteria, scope, frequency and methods, impartiality, and follow-up verification. The product-tracing approach below is a practical example, not a statutory sample size or the only audit method. See the KGMP preparation guide for the quality-system context.

Choose samples using process status and importance

Consider the status and importance of processes and previous audit results. Useful candidates include material from a recently changed supplier, a product with repeated complaints, or a lot produced after a process adjustment. Selecting only convenient, routine records can overlook vulnerable connections.

Tracing one product provides depth but does not establish conformity for every product and process. Record why the sample was chosen, what it covers, its limitations, and conditions for expanding it. If an issue appears, decide whether other records from the same period or supplier need examination, and retain the reasoning.

Connect the beginning and end of a lot

Adapt these questions to the product and the organization’s activities. Importers should distinguish manufacturing activities they do not perform from the evidence they need from the manufacturer.

Compare dates and revisions, not just record numbers. Instructions used before approval, equipment outside its calibration range, or returns disconnected from investigations may reveal problems. Confirm discrepancies through responsible staff and objective records; do not turn an assumption into a nonconformity.

Separate the criterion, the observed fact and the implication

“Poor document control” does not explain what needs correction. Identify the applicable criterion, the record or observation, and the specific gap. Distinguish improvement suggestions from failures to meet requirements, and follow the organization’s classification process.

If an obsolete instruction was used, identify the document, revision, actual use date and affected products. Investigate whether this was a clerical issue or different operating conditions before concluding. Preserve the identity and authorized handling of photographs or copies so another reviewer can verify the same facts.

Action completion and effectiveness need separate attention

Assign responsibility so necessary correction and corrective action address the nonconformity and its causes without undue delay. Removing an obsolete instruction differs from understanding why it remained available and preventing recurrence. Review distribution, withdrawal, training or system controls according to the cause.

Follow-up must include verification of the action and reporting of results. Uploading a new document alone is weaker evidence than showing the next operation used the correct revision. The KGMP corrective-action response guide explains how to organize supporting evidence.

Prepare evidence access and auditor independence

Ensure auditors do not audit their own work and have appropriate competence and impartiality. A small department should not simply relabel self-checking as an internal audit. Agree on criteria, scope, samples, timing, interviewees and record access so the audit is not consumed by searching for files.

Bring recent change, complaint and nonconformity lists, plus one product’s purchasing-to-release records, to an internal-audit preparation review. Clare Partners can help organize connections and outstanding actions. Retain conclusions, responsible approvals and follow-up verification so the audit informs the next improvement plan.

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Source checked: 2026-09-28. Section 8.2.4, Internal audit, in Annex 2 of the MFDS medical-device manufacturing and quality management standard, Notice 2026-46. Sample choices and preparation steps are practical recommendations.