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ForumsCOA & Analytical TestingMass spectrometry for peptide identity verification — March 2026 Page 5

Mass spectrometry for peptide identity verification — March 2026

hannah_MT Sat, Jul 12, 2025 at 7:00 AM 26 replies 1,892 viewsPage 5 of 6
Dr.SportsMedIN
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Jul 18, 2025 at 9:10 PM#21
EndoResFellow said:
It is worth asking what the claim would look like if it were false.

There is a second half to this that has not been said yet. The version of this that has an answer is narrower than the version being asked. Narrow it and it becomes tractable; leave it broad and the thread will produce nine confident and incompatible replies.

25 23lucas_SP_BR, lisa_labSD, adam_van and 22 others
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BiostatsBrad
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Jul 19, 2025 at 9:32 AM#22

Adding the numbers, since they settle part of this. One habit that pays for itself: post the method alongside the number. A figure without its method cannot be checked, and an unchecked figure is how this community accumulates folklore.

26 24Dr.BariatricHTX, LindaRN_retired, tommy_boulder and 23 others
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TrialTracker_MD
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Jul 19, 2025 at 9:54 PM#23

Following on from EndoResFellow — and this may be the naive question:

Was that from a primary source or from a summary of one?

Last edited: Jul 20, 2025 at 2:54 AM
27 0maya_sedona, stefan_berlin, Dr.EM_Chicago and 24 others
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SkepticalSean
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Jul 20, 2025 at 10:15 AM#24
BiostatsBrad said:
One habit that pays for itself: post the method alongside the number.

I read this differently from BiostatsBrad, on substance rather than tone. Filing an objection on the n=1 problem. Personal experience is genuine evidence about one person and very weak evidence about anybody else, and this thread keeps promoting the first into the second.

Last edited: Jul 20, 2025 at 2:15 PM
28 1tammy_FL, Dr.LipidDallas, alex_tucson and 25 others
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SaraMom3
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Jul 20, 2025 at 10:36 PM#25
BiostatsBrad said:
One habit that pays for itself: post the method alongside the number.

Right, and the exception is worth naming rather than left implied, because the exception is where people get into trouble.

29 2ZaraB_AL, JakeSmashed95, NauseaFreeNow and 26 others
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