Sourcing · Vendor reports

Filing a first vendor report: a worked example

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

n.petrovTL218 Jan 2025#1

Filing a first vendor report: a worked example Writing it up because I had to work it out twice and would rather nobody else did.

Working notes on filing a first vendor rather than a conclusion. I would rather post the reasoning while it can still be corrected than post the answer once I am committed to it.

Everything below is checkable. Where I have taken a figure from somewhere else I have said where; where I have estimated, I have said that too.

3 likes 18mo

d.nwosuTL216 Feb 2025 · edited#2

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

Date the report: when the analysis was done matters. Material can degrade in storage. A report from two years ago is still useful but is not evidence about the current state of the same supplier's stock.

Worth one more sentence than it usually gets.

0 likes 17mo

s.poulsenTL3Regular8 Mar 2025#3

The format we ask for is compound, lot, testing service, method as reported, result, and the certificate figure for the same lot. A report missing any of those goes to the discussion rather than the record.

A modest claim, modestly supported.

17 likes 17mo

e.tammTL227 Mar 2025#4

Selective submission and selective reporting are the two easiest ways for a result to be shaped, and blinding addresses the first while a commitment to post addresses the second.

7 likes 16mo

k.farrugiaTL3Regular13 Apr 2025#5

Worth separating two things that the opening post runs together.

Report the certificate figure alongside the independent one. The comparison is the point and it is the part most often omitted.

On reflection I would soften that slightly.

3 likes 15mo

m.yildizTL229 Apr 2025#6

n.petrov, post #1: Filing a first vendor report: a worked example Writing it up because I had to work it out twice and would rather nobody else did. Working notes on filing a first vendor rather than a conclusion. I would rather post the reasoning while it can still be corrected than post the answer once I am committed to it. Everything below is… Go to post

Post #5 is right about the mechanism and I think understates the practical bit.

A difference inside method repeatability is not a disagreement. Saying so in your own report prevents somebody else reading it as one.

If that reads as pedantic, it is, and it has saved me twice.

0 likes in reply to #1 15mo

This topic was referenced in

One lot is one lot: when a report becomes a patternSourcing › Vendor reports · 2 replies

Moved from Logistics by dr_okonkwo. 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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