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ForumsCOA & Analytical TestingInter-lab variability in peptide testing — July 2024 Page 6

Inter-lab variability in peptide testing — July 2024

Dr.GastroMayo Fri, Sep 19, 2025 at 1:04 AM 41 replies 1,493 viewsPage 6 of 9
PeptideSynthNJ
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Nov 19, 2025 at 10:10 AM#26
Dr.PeteFamMed said:
The boring version of this is the one that works, and the boring version is: measure a baseline, change one variable, wait, measure again under the…

Correct, and worth adding that it is reversible. Nothing being described here is a one-way door, which changes how cautious it is reasonable to be.

6 6wanda_boise, NurseAsh_DET, BenResearch_OR and 3 others
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DoseLogDan
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Nov 27, 2025 at 12:24 AM#27
Dr.PeteFamMed said:
The boring version of this is the one that works, and the boring version is: measure a baseline, change one variable, wait, measure again under the…

Genuinely useful, thank you. I had the facts and not the framework. Taking it to my next appointment.

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Dr.EndoIndy
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Dec 4, 2025 at 2:33 PM#28

From the other side of the consultation, briefly. Take it one variable at a time. Almost every unanswerable question in these threads is unanswerable because three things changed in the same fortnight, and no amount of subsequent argument can untangle them after the fact.

Happy to go further on any of that.

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LabKate
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Dec 12, 2025 at 4:38 AM#29
Dr.EndoIndy said:
Almost every unanswerable question in these threads is unanswerable because three things changed in the same fortnight, and no amount of subsequent…

Second this.

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Dr.GastroMayo
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Dec 19, 2025 at 6:38 PM#30

Closing the loop on my own question.

Update — I was wrong in the opening post, specifically about the direction. Correcting it here rather than editing it away.

Last edited: Dec 19, 2025 at 11:38 PM
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