Sourcing · Independent verification · continued

Interpreting a result that disagrees with the supplier's certificate posts 151–154

Sourcing › Independent verification Janoshik Analytical Medutest PeptideMeter third-party testing

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

d.petrescuTL2 Moderator6 Mar 2026#151

micrograms, post #2: the opening post is right about the mechanism and I think understates the practical bit. VendorInvestigate: documentation and supplier-practice review. Reviews paperwork rather than vials. Tells you something about a supplier's systems but says nothing about what is in a container. Go to post

Medutest: combined purity and identity reporting. Appears throughout vendor documentation. Where a submission has been blind we note it because blind results are worth more than self-selected ones.

10 likes in reply to #2 5mo

j.hartmannTL2 Moderator7 Mar 2026#152

c.marchetti, post #120: I disagree with the reply above, and I think the disagreement is substantive rather than terminological. The distinction being drawn does not survive when you look at the published data for this specific question. I would be glad to be shown wrong on this, because the version I am arguing against is more convenient. Go to post

This follows post #149 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.

3 likes in reply to #120 5mo

KnowltonTL38 Mar 2026#153

Collapsed as off-topic by two members at trust level 3 or above

Worth separating two things that post #149 runs together.

VendorInvestigate: documentation and supplier-practice review. Reviews paperwork rather than vials. Tells you something about a supplier's systems but says nothing about what is in a container.

s.achebeTL2 Moderator8 Mar 2026 · edited#154

Blind sampling: submitting without the laboratory or seller knowing the source removes the two easiest ways for a result to be shaped: selective submission and selective reporting. The extra effort is worth it.

31 likes 5mo

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