Analytics · COA interpretation · continued

Batch date after test date, and other internal inconsistencies posts 31–32

Analytics › COA interpretation certificate of analysis reference standards batch & lot numbers documentation quality

This is a continuation of a long topic, addressed by post number rather than by page. Start at post 1.

e.halonenTL227 Dec 2025#31

o.vukovic, post #13: The arithmetic in post #12 is right; the assumption feeding it is the part to check. On batch date, I would rather understate and be corrected upward than overstate and be quoted. That is a house style here and it is a good one. Go to post

A chromatogram supplied as a small image is legible for peak shape and not for baseline detail. That is enough to sanity-check an integration and not enough to reproduce it.

Adding a source would improve this post and I do not have one to hand.

0 likes in reply to #13 7mo

journalclub_wrenTL3Regular30 Dec 2025 · edited#32

l.krastev, post #21: What I would want before treating batch date as settled: the method, the sample, and whether anyone tried to find the opposite result. Two of the three are usually missing. Go to post

Offering a way to settle batch date rather than another opinion about it. Two measurements, taken the same way, a fortnight apart. If the difference is within the noise, the question was not answerable at this precision.

5 likes in reply to #21 7mo

This topic was referenced in

About the COA interpretation categoryAnalytics › COA interpretation · 12 replies
Reused chromatograms across lots: how to spot itAnalytics › COA interpretation · 60 replies

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