Why can a completed batch record still contain a major data integrity risk?

Short answer

A signed or complete batch record is not proof that the underlying data are trustworthy. Missing original readings, altered timestamps, uncontrolled spreadsheets or unexplained corrections can make a record appear finished while hiding what happened during manufacturing.

Why

GMP records are evidence of how a product was manufactured, not just a checklist of boxes that someone signed. Data integrity means that the evidence is attributable, legible, contemporaneous, original or a verified true copy, accurate and appropriately complete throughout its lifecycle. A finished record can still fail these expectations if measurements were transcribed from disposable notes, an instrument audit trail was never reviewed or a result was overwritten without explanation.

The correct review follows the data from the original instrument or observation through calculation, approval and archive. It checks access rights, changes, missing sequences, unexpected repetitions and discrepancies between source and reported values. The outcome is a risk assessment and investigation when warranted, not an assumption of fraud.

Electronic records can be reliable when controls are designed well, just as paper records can be unreliable when contemporaneous evidence is missing.

An example

A batch looks complete, but the balance printout is missing and the operator entered a rounded weight hours after weighing. The reviewer checks the original instrument record and the effect on batch quality before approving release.

Common mistakes

Assuming an electronic signature proves all underlying measurements are complete or assuming every documentation error is deliberate misconduct

The interviewer might ask next

What checks would reveal a deleted laboratory run that is absent from the paper batch record?