How Janoshik, Medutest, PeptideMeter and VendorInvestigate differ posts 121–131

Adding the measurement that post #120 says would settle it.

Medutest: combined purity and identity reporting. Appears throughout vendor documentation. Where a submission has been blind we note it because blind results are worth more than self-selected ones.

Something worth flagging about Janoshik: the strongest-sounding claims in this thread are the ones with no source attached, which is the usual pattern and not a coincidence.

Second-hand on Janoshik, so weight it accordingly — someone whose method I trust told me this and I have not verified it myself.

I had written a reply contradicting post #120 and deleted it. Here is what survived.

A record with four results over sixteen months is a thin record rather than a bad one, and the honest description says which.

The arithmetic in post #122 is right; the assumption feeding it is the part to check.

Janoshik has a well-known answer and a correct answer, and the interesting work is establishing that they are the same. Nobody has done that here yet.

Answering the question post #124 raises rather than the one it answers.

Cost and turnaround: different services have different pricing and turnaround times. Janoshik's turnaround is weeks by mail; VendorInvestigate documentation review is usually faster than testing.

Reframing Janoshik slightly, because I think the disagreement is about the question rather than the answer. If the question is "does it happen", yes. If it is "how often", nobody here knows.

The documentation on Janoshik is better than this thread and I say that as someone who has posted in the thread.

Repeat determination on the same product line months apart is the measurement that speaks to consistency, and consistency is what most buyers actually want.

Take the reasoning and check the arithmetic; I do not always get it right.

That reframing is the whole thing. The facts I already had.

Worth separating two things that post #127 runs together.

It does not extend to lots nobody has seen, it is not a recommendation, and it says nothing about anything other than what was measured.