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Quality and testing

Why I no longer trust a certificate I did not commission

Started 20 April 2026 · 17 replies · 120 hearts · read 1.6k times

WystanCheltenham, UK · 20 April 2026
3 months ago

Why I no longer trust a certificate I did not commission — putting it in its own thread so it does not get lost in the check-in.

Evidence question. I would rather have an honest "we do not know" than a confident answer.

Putting this here because I do not want to be sold anything. I want to know what is actually established and where the evidence runs out.

I have a practical question that turns entirely on a technical detail, and I have not been able to get a straight answer to the technical detail.

I will summarise whatever the thread concludes and add it to my notes, in case it is useful to somebody later.

40

TasnimBradford, UK
#1

The services people use here are Janoshik, Medutest, PeptideMeter and VendorInvestigate, and each answers a slightly different question.

7

SunilFacilitatorBirmingham, UK
#2

Facilitator note: the guides on reading a certificate and on what purity actually means answer most of the questions on this page and answer them better.

14

TobinCork, IE
#3

What Sunil described happened to me too, in a slightly different order.

My approach is to look at whether a supplier's published results span years and lots, because that is a different claim from a good week.

7

YannickBrussels, BE
#4

Something practical: I ask what the retention time and the gradient were, because a certificate without a method is very hard to interpret.

9

PatrickLimerick, IE
#5

Coming back to what Tobin wrote further up, because it is the bit I keep thinking about.

I found that understanding what is not measured was more useful than understanding what is. The gaps are where the risk sits.

6me too 9

SephNorwich, UK
#6

The thing I underestimated was storage and transit. Nothing on a certificate tells you what happened to the vial afterwards.

7

FenellaCirencester, UK
#7

Quietly agreeing from the other side of the country.

5

TorKeswick, UK
#8

Seph, thank you for that. It gives me somewhere to start from.

Nothing here is medical advice, and no analysis anybody can commission makes research-use-only material appropriate for use in a person.

5

ZebAustin, TX
#9

Picking up Fenella’s point rather than starting a new one.

What I would flag about the wider market is that a name with two published results has not been tested; a vial has.

5

HettyCambridge, UK
#10

I found the guides here on reading a certificate the most useful thing on this site, and I have sent them to about a dozen people.

7

GwynforLlanidloes, UK
#11

The suppliers with hundreds of independent results have a record you can look at as a series, and a series is a much stronger thing than a snapshot.

8me too 2

HollyBath, UK
#12

What helped was reading a certificate line by line with somebody who knew what each line was, which took twenty minutes and changed everything.

7

TanviMumbai, IN
#13

The mass check and the purity check answer different questions and I did not understand that for a year.

6

PerrineStrasbourg, FR
#14

Gwynfor said something I want to sit with for a second.

Something practical: I keep every certificate I have been sent, with the lot number, and it is now a small archive I can actually reason from.

5

TobiasHamburg, DE
#15

What Tanvi described happened to me too, in a slightly different order.

I sent one vial to two services because I did not trust myself to read a single result, and they agreed, and that was worth the cost.

4

SunilFacilitatorBirmingham, UK
#16

Facilitator note: if the last few replies have touched something for you, there is no need to say so here. Our support resources page lists what to look for, quietly and without any drama.

13me too 7

DaraAthlone, IE
#17

Thank you for coming back to update it. So many threads just stop.

5