Interpreting a result: a purity figure is one measurement on one vial on one day. Agreement across two services is much stronger. A single high number does not establish a pattern.
28 likes 6mo
Topic summary
[2026 update] What a purity-only report leaves out
This is a generated summary. It shows the 9 most-liked posts from a topic of 104, 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.
On post #10 — agreed on the reasoning, with one qualification.
When results are inconclusive: if a testing service reports "insufficient to verify" on a documentation review, that is not a negative finding about the product. It means the documents did not contain enough to check.
32 likes 6mo
I disagree with the reply above, and I think the disagreement is substantive rather than terminological.
The distinction being drawn does not survive when you look at the published data for this specific question. I would be glad to be shown wrong on this, because the version I am arguing against is more convenient.
28 likes 5mo
Blind sampling: submitting without the laboratory or seller knowing the source removes the two easiest ways for a result to be shaped: selective submission and selective reporting. The extra effort is worth it.
32 likes 4mo
t.nardone, post #25: I read post #23 twice before replying, because I had assumed the opposite. VendorInvestigate: documentation and supplier-practice review. Reviews paperwork rather than vials. Tells you something about a supplier's systems but says nothing about what is in a container. Go to post
When results are inconclusive: if a testing service reports "insufficient to verify" on a documentation review, that is not a negative finding about the product. It means the documents did not contain enough to check.
For anyone arriving from a search: the marked solution above is the direct answer, and the replies underneath it add the caveats that make it safe to use.
28 likes 3mo
Read the full topic (104 posts)
This topic was referenced in
- Turnaround times and what they mean for a decisionSourcing › Independent verification · 4 replies
- How Janoshik, Medutest, PeptideMeter and VendorInvestigate differ — does this still hold?Sourcing › Independent verification · 28 replies
- Turnaround times and what they mean for a decision — one year onSourcing › Independent verification · 29 replies
Suggested topics
| Topic | Participants | Replies | Views | Activity |
|---|---|---|---|---|
|
Submitting a sample: the process end to end
On the subject in the title: Submitting a sample: the process end to end Working notes rather than a conclusion. I would like to talk about documentation quality as a signal, separately from product quality.…
|
+99 | 114 | 29k | 21h |
|
Blind submission and why it changes minds
Blind submission and why it changes minds — setting out what I have, and where I think it stops being reliable. Structured report rather than an opinion, following the format the maintainers asked for.…
|
+91 | 96 | 1.1k | 21mo |
|
Publishing an inconvenient result: a case study
On the subject in the title: Publishing an inconvenient result: a case study Working notes rather than a conclusion. Structured report rather than an opinion, following the format the maintainers asked for.…
|
+59 | 70 | 992 | 11mo |
|
Chain of custody for a sample you posted yourself — one year on
Posting this under the heading it deserves: Chain of custody for a sample you posted yourself — one year on Everything below is what sits behind that. Structured report rather than an opinion, following the…
|
+28 | 32 | 50k | 15h |
|
Chain of custody for a sample you posted yourself
Chain of custody for a sample you posted yourself Writing it up because I had to work it out twice and would rather nobody else did. A logistics question, since the answers here are usually better than…
|
2 | 7.3k | 5h |
Related topics — sharing the tags PeptideMeter, third-party testing, Janoshik Analytical
| Topic | Participants | Replies | Views | Activity |
|---|---|---|---|---|
|
Revisiting: The report format the maintainers ask for, and why each field is there
Posting this under the heading it deserves: Revisiting: The report format the maintainers ask for, and why each field is there Everything below is what sits behind that. Structured report rather than an…
|
+100 | 108 | 57k | 1d |
|
What consumer-accessible tests can and cannot determine — a second dataset
What consumer-accessible tests can and cannot determine — a second dataset I have a specific reason for asking rather than idle curiosity, and the context is below. Posting the method first, because I know…
|
+117 | 131 | 45k | 10h |
|
One lot is one lot: when a report becomes a pattern — the long version
One lot is one lot: when a report becomes a pattern — the long version — setting out what I have, and where I think it stops being reliable. Structured report rather than an opinion, following the format the…
|
+137 | 152 | 46k | 16mo |
|
A comparison of home results against a laboratory result on the same vial — does this still hold?
A comparison of home results against a laboratory result on the same vial — does this still hold? I have a specific reason for asking rather than idle curiosity, and the context is below. Working through the…
|
+2 | 6 | 15k | 11h |
|
What a simple presence test is genuinely useful for
What a simple presence test is genuinely useful for — that is the question, and I have not found it answered plainly anywhere I have looked. Working through the identity arithmetic and I would like it…
|
2 | 58 | 1d |