Start with the identity of the report
Before looking at an individual result, establish what the document describes. Find the sample name, the lot or batch identifier, the issuing laboratory and the report date. Keep the original document with your laboratory purchasing records so the context stays attached to the result.
Match the lot, not just the name
A certificate for one sample does not document every product with the same compound name. Compare the identifier on the supplied material with the identifier on its report. If either is absent or inconsistent, record the discrepancy and request clarification before relying on the document.
Read the method alongside the number
A result needs its method, units and reporting context. Review what was measured and what the report actually states. Do not treat a single percentage as a substitute for the full analytical record, or assume that an unreported test was performed.
Keep uncertainty visible
Missing documentation should remain visibly missing. A blank field is not a passing result. Keep open questions in your material review and resolve them with the supplier or issuing laboratory rather than filling gaps from a different lot.