Topic summary

One lot is one lot: when a report becomes a pattern — the long version

Sourcing › Vendor reports third-party testing Janoshik Analytical certificate of analysis batch & lot numbers documentation quality Closed

This is a generated summary. It shows the 9 most-liked posts from a topic of 153, in their original order, with the accepted answer included where one exists. It is a reading aid and it will miss nuance — the full topic is the record.

GDashwoodTL3Regular14 Mar 2025#4

Disputed records: when a result disagreed and was not explained, the record says disputed and stays that way. We do not remove inconvenient history; we document it.

31 likes 16mo

j.vandermolenTL3Regular16 Mar 2025#36

Lot matching: confirm the lot number on the certificate matches the lot number on the vial. A result from a different lot is not evidence about your vial.

28 likes 16mo

bias_varianceTL4Biostatistician16 Mar 2025#43

a.asante, post #21: Lot matching: confirm the lot number on the certificate matches the lot number on the vial. A result from a different lot is not evidence about your vial. Go to post

Blind submission is worth the effort: have someone else relabel the sample so neither you nor the laboratory knows which supplier it came from until the result is back. Blind results change minds; self-selected results do not.

30 likes in reply to #21 16mo

p.amankwahTL2 Moderator16 Mar 2025#50

FFaulkner, post #30: This follows post #27 rather than contradicting it. For anyone arriving from a search: the marked solution above is the direct answer, and the replies underneath it add the caveats that make it safe to use. Go to post

post #49 answers the question as asked. The question underneath it is different.

Dosing and purity: a vial that is 99% pure might contain 80% of its label claim if the other mass is water, counter-ion, and excipient. Purity and content are different. Both matter for different reasons.

31 likes in reply to #30 16mo

a.cardosoTL2 Moderator16 Mar 2025#53

Temporal patterns: if results from a supplier were good two years ago but have deteriorated recently, that is information. If they have been consistent over years, that is also information.

32 likes 16mo

c.okaforTL3Regular17 Mar 2025#78

a.cardoso, post #53: Temporal patterns: if results from a supplier were good two years ago but have deteriorated recently, that is information. If they have been consistent over years, that is also information. Go to post

Two things before anyone answers the substance.

First, the context in the first post is clear and specific. Second, the question is framed so that an answer can actually address it. Both are the norm here and both matter more than they sound.

31 likes in reply to #53 16mo

NorringtonTL3Regular17 Mar 2025#83

I read post #81 twice before replying, because I had assumed the opposite.

Having read the exchange above, I think I was wrong earlier in this topic and I want to say so plainly rather than quietly editing.

The correction was fair and I had been repeating something I had not checked carefully enough.

32 likes 16mo

v.kirchnerTL2 Moderator18 Mar 2025#112

post #111 is right about the mechanism and I think understates the practical bit.

Lot matching: confirm the lot number on the certificate matches the lot number on the vial. A result from a different lot is not evidence about your vial.

33 likes 16mo

s.perrinTL2 Moderator19 Mar 2025 · edited#137

Lot matching: confirm the lot number on the certificate matches the lot number on the vial. A result from a different lot is not evidence about your vial.

29 likes 16mo

Read the full topic (153 posts)

This topic was closed 45 days after the last reply. Closing is automatic for quiet topics so that a settled answer does not collect new questions underneath it. If you have a follow-up, open a new topic and link back to this one — that keeps both readable and gives your question its own title.

Moved from Regulatory by t.vasquez. Category placement is not obvious from outside and getting it wrong is expected. This topic will get better answers here. The move is recorded in the public log citing R7.

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