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Evidence-based GLP-1 & peptide discussion since 2023
ForumsCOA & Analytical TestingInter-lab variability in peptide testing — July 2024 Page 9

Inter-lab variability in peptide testing — July 2024

Dr.GastroMayo Fri, Sep 19, 2025 at 1:04 AM 41 replies 1,493 viewsPage 9 of 9
josh_phd_bmore
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Mar 12, 2026 at 5:33 AM#41
PeptideSynthNJ said:
If you are comparing against somebody else’s result, check that you are comparing the same measurement taken the same way.

Worth saying that the confident version of this is more useful to the person writing it than to the person reading it.

Last edited: Mar 12, 2026 at 7:33 AM
49 24NurseKim_ATL, paul_denver, TinaHashiRN and 46 others
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andrew_nyc
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Mar 19, 2026 at 3:39 PM#42
PeptideSynthNJ said:
If you are comparing against somebody else’s result, check that you are comparing the same measurement taken the same way.

Fair, and it stops being fair at the extremes. The middle of the range is well understood; the ends are where the honest answer is that nobody knows.

Last edited: Mar 19, 2026 at 8:39 PM
48 23Dr.NateNeph, PharmD_Rodriguez, julia.endo and 45 others
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Admin
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Mar 27, 2026 at 1:40 AM#43

Moderator note: the sourcing question belongs in the vendor section and has been split out.

47 22RegAffairsDC, BiostatsBrad, PeptideSynthNJ and 44 others
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LindaRN_retired
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Apr 3, 2026 at 11:37 AM#44

Clinical perspective, offered as context rather than as advice. It helps to ask what evidence would change your mind before you look at any. If nothing would, the discussion is not about evidence, and it is better to say so early than to spend nine posts discovering it.

Last edited: Apr 3, 2026 at 2:37 PM
46 21LondonLisa, mike_nyc, VendorMark and 43 others
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tony_orlando
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Apr 10, 2026 at 9:30 PM#45
LindaRN_retired said:
It helps to ask what evidence would change your mind before you look at any.

Same experience, arrived at from the opposite direction. The detail I would add is minor and it is already implied above.

45 20KetoKyle, CanadaChris, ZaraB_AL and 42 others
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