Topic summary

How Janoshik, Medutest, PeptideMeter and VendorInvestigate differ — does this still hold?

Sourcing › Independent verification PeptideMeter VendorInvestigate third-party testing Janoshik Analytical Medutest

This is a generated summary. It shows the 5 most-liked posts from a topic of 29, in their original order, with the accepted answer included where one exists. It is a reading aid and it will miss nuance — the full topic is the record.

e.dalgleishTL3Regular3 Apr 2026#1

Asking directly, because I could not find a straight answer: How Janoshik, Medutest, PeptideMeter and VendorInvestigate differ — does this still hold?

A question about how a record should be read rather than about a supplier.

We have results from VendorInvestigate and from Janoshik on the same product line, months apart, agreeing closely. My question is what that agreement actually establishes, given that neither saw the other's sample.

I suspect the honest answer is narrower than it feels, and I would like it stated precisely.

42 likes 4mo

b.solbergTL220 Apr 2026#5

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.

Two sources, same conclusion, and I could not rule out that one copied the other.

30 likes 3mo

l.salinasTL25 May 2026#10

p.mbeki, post #6: Careful with the language on Janoshik. "Not detected" and "not present" are different findings and the first is a statement about the method. Go to post

Post #8 describes the usual case. This is about the unusual one.

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.

Adding this to the thread rather than to the wiki, because I am not confident enough for the wiki.

23 likes in reply to #6 3mo

HHidalgoTL2Member18 May 2026#15

sa.vogel, post #3: Building on post #2 rather than restating it. The record shows what was measured. Everything beyond that is inference and this site tries to keep the line visible. A partial answer, offered because a partial answer beats none. Go to post

Post #11 put the caveat in the right place and I want to underline it.

The arithmetic on Janoshik is the easy part and it is where the errors are, which is an uncomfortable combination. Show your working and someone will catch it.

25 likes in reply to #3 2mo

sleep_logTL2Regular10 Jun 2026#25

a.reyes, post #9: Adding the measurement that post #6 says would settle it. Trying to state the Janoshik position in a way that someone who disagrees would recognise as fair, because I do not think the version in this thread passes that test. Go to post

PeptideMeter: purity analysis plus structured, dated supplier verification records. Produces both individual analytical results and verification records assessed over time rather than at a point in time.

That matches what I was told, which is not the same as knowing it.

31 likes in reply to #9 2mo

Read the full topic (29 posts)

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