Historical results remain evidence of performance against the requirements then applied, but they do not automatically demonstrate conformity with revised requirements.
Preserve the original meaning
A historical pass should remain linked to the inspection requirement, method, limits, and revision in force when the inspection occurred. It means the examined item or sample met that earlier basis within the recorded scope. Updating the criterion does not make the old result false, but it may change what can reasonably be concluded from it today. Replacing the old revision number with a new one would rewrite the evidence rather than interpret it.
Determine whether results are comparable
Old and new results may be directly comparable only when the relevant definitions remain equivalent. Review what changed: the characteristic being examined, acceptance limit, instrument or method, sample selection, inspection conditions, defect classification, or decision rule. A stricter limit may allow existing raw measurements to be reassessed. A changed method may make retrospective comparison unreliable because the required observation was never collected.
Choose the correct route
If original raw data are complete and compatible with the new criterion, a documented desk review may establish whether those data satisfy the revised requirement. If necessary information is missing, representative retained samples may require reinspection where valid and available. When neither route is possible, the historical result should remain valid only under its original revision, with current compliance left unverified. A new sampling decision should identify its own scope; the NIST/SEMATECH e-Handbook emphasizes that sampling supports lot disposition rather than an exact estimate of every unit’s quality.
Report versions and effective scope
A clear record names the old and new revisions, their effective dates, affected SKUs or batches, the nature of the change, the comparability decision, and any reassessment performed. The conclusion should distinguish passed under the former requirement, reassessed and passed under the new requirement, and not evaluated under the new requirement. This prevents a historical pass from being silently extended beyond the evidence that produced it.