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

Inter-lab variability in peptide testing — July 2024

sean_dublin Mon, Feb 23, 2026 at 12:36 PM 30 replies 1,343 viewsPage 6 of 6
Dr.SleepRoch
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Apr 29, 2026 at 4:48 AM#26

Clinical perspective, offered as context rather than as advice. The honest answer is that the effect is real, the magnitude is contested, and the individual variation is larger than either. Those three things can all be true at once, and most arguments here are two people holding different parts of that.

Last edited: Apr 29, 2026 at 8:48 AM
47 20sarah_TO, wendy_avl, jason_paloalto and 44 others
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lisa_labSD
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May 7, 2026 at 7:06 AM#27
Dr.SleepRoch said:
The honest answer is that the effect is real, the magnitude is contested, and the individual variation is larger than either.

Same pattern here, and in the same order.

48 21maya_sedona, stefan_berlin, Dr.EM_Chicago and 45 others
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Dr.KarenChen
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May 15, 2026 at 9:18 AM#28
Dr.SleepRoch said:
The honest answer is that the effect is real, the magnitude is contested, and the individual variation is larger than either.

Adding the part of the answer the thread has not reached. Worth answering the question that was asked rather than the one behind it. The narrow version usually has an answer; the broad version usually does not, and answering the broad one is how a thread stops being useful.

49 22TomFromTexas, mike.trainer_LA, sarah_nash92 and 46 others
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lucas_SP_BR
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May 23, 2026 at 11:26 AM#29

Adding the numbers, since they settle part of this. For anyone reading later: the numbers in this thread are worth checking against a primary source before you act on them, including mine. Half the figures circulating in this community trace back to a secondary summary that dropped a qualifier.

Last edited: May 23, 2026 at 1:26 PM
50 23KarenAZ_mom, zoe_NC, Dr.ObesityLA and 47 others
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sean_dublin
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Dublin, IE
May 31, 2026 at 1:29 PM#30

Reporting back.

Reporting back for the archive rather than for the thread: I did the narrow version of what was suggested, gave it the full interval, and it settled. Posting it because threads without a follow-up are half a thread.

22 20quinn_sf, NurseLeah_Nash, gary_naperville and 19 others
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