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ForumsCOA & Analytical TestingMass spectrometry for peptide identity verification — March 2026 Page 7

Mass spectrometry for peptide identity verification — March 2026

TirzTom Fri, Jan 9, 2026 at 3:52 PM 40 replies 1,536 viewsPage 7 of 8
TrialTracker_MD
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Feb 14, 2026 at 10:02 AM#31

Adding the numbers, since they settle part of this. If you are comparing against somebody else’s result, check that you are comparing the same measurement taken the same way. Most of the apparent contradictions in these threads dissolve at that step.

39 12Dr.EM_Chicago, pete_RVA, CarlaRPh_TPA and 36 others
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emma_london
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Feb 17, 2026 at 3:18 AM#32

One thing that is still open after Dr.LipidDallas’s answer:

What did you change at the same time, and can you separate the two now?

40 13mike.trainer_LA, sarah_nash92, FitDadDave and 37 others
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Dr.SleepRoch
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Feb 19, 2026 at 8:32 PM#33
TrialTracker_MD said:
If you are comparing against somebody else’s result, check that you are comparing the same measurement taken the same way.

This is where I part company with the consensus forming above. The objection nobody has made: this only works if the measurement is doing what we assume it is doing, and that assumption has not been tested here.

41 14Dr.NephBHM_UK, kim_atl_prep, sarah_TO and 38 others
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traveltech_sara
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Feb 22, 2026 at 1:44 PM#34
TrialTracker_MD said:
If you are comparing against somebody else’s result, check that you are comparing the same measurement taken the same way.

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.

Last edited: Feb 22, 2026 at 4:44 PM
42 15NurseAsh_DET, BenResearch_OR, MikeKY_noInsulin and 39 others
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DataDave
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Feb 25, 2026 at 6:55 AM#35
TrialTracker_MD said:
If you are comparing against somebody else’s result, check that you are comparing the same measurement taken the same way.

That reframing is the part I needed. Taking it to my next appointment.

Last edited: Feb 25, 2026 at 7:55 AM
43 16Dr.GutHealth, amsterdam_pete, LondonLisa and 40 others
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