Topic summary

Revisiting: Aggregate verification data across the directory, with caveats

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

This is a generated summary. It shows the 5 most-liked posts from a topic of 27, 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.

p.mbekiTL22 Feb 2025#1

Revisiting: Aggregate verification data across the directory, with caveats — setting out what I have, and where I think it stops being reliable.

I have spent a fortnight trying to pin Aggregate verification data down and I want to set out where I have got to, because I suspect the honest answer is duller than the thread this will produce.

What I have: a consistent observation across a small number of cases, collected the same way each time. What I do not have: any controlled comparison, or any reason to think my cases are representative.

The specific question is whether the pattern survives once the obvious confounder is removed. I cannot remove it with what I have.

29 likes 18mo

e.verhoevenTL214 Feb 2025#8

Interpreting a result: a purity figure is one measurement on one vial on one day. Agreement across two services is much stronger. A single high number does not establish a pattern.

I would rather post the uncertainty than round it away.

31 likes 17mo

ca.haddadTL218 Feb 2025#11

Post #8 answers the question as asked. The question underneath it is different.

Adding a null result on Aggregate verification data. I looked, carefully, and found nothing, and null results deserve posting precisely because they never are.

28 likes 17mo

n.szaboTL223 Feb 2025 · edited#15

The record shows what was measured. Everything beyond that is inference and this site tries to keep the line visible.

I looked this up rather than remembered it, which is the right order.

21 likes 17mo

h.fonsecaTL27 Mar 2025#26

Nobody has said the unglamorous part of Aggregate verification data yet, so: most of the variation is explained by things that are boring to write about and easy to check.

29 likes 17mo

Read the full topic (27 posts)

This topic was referenced in

Splitting a vial for two laboratories: how to do it without ruining bothSourcing › Independent verification · 70 replies
Turnaround times and what they mean for a decision — one year onSourcing › Independent verification · 29 replies
Publishing an inconvenient result: a case study — the long versionSourcing › Independent verification · 74 replies

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