Worth separating two things that the opening post runs together. What I want from this blind submission thread is the list of things that would need to be true for the claim to hold. If we can write that list, we can check it.
Blind submission and why it changes minds — setting out what I have, and where I think it stops being reliable.
What changes if the standard account of blind submission is wrong? I ask because I have been treating it as settled and I noticed this week that I could not say why.
Working through the consequences rather than the evidence, since others here are better placed on the evidence.
Worth separating two things that the opening post runs together.
What I want from this blind submission thread is the list of things that would need to be true for the claim to hold. If we can write that list, we can check 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.
Written from notes rather than memory, which is why the numbers are specific.
I have no financial interest in anything named in this thread and I want to say so before I comment on blind submission, because it is the sort of subject where it matters.
Taking post #7 at face value and following it one step further.
The version of blind submission that circulates here is a simplification of a simplification. It is not wrong, but it has lost the conditions under which it holds, and those conditions are where the interesting cases live.
Building on post #8 rather than restating it.
What I would want before treating blind submission as settled: the method, the sample, and whether anyone tried to find the opposite result. Two of the three are usually missing.
Post #10 put the caveat in the right place and I want to underline it.
Reading back through the blind submission threads from last year, the same three questions come up every time and only one of them has ever been answered properly. That seems like a documentation gap rather than a knowledge gap.
The record shows what was measured. Everything beyond that is inference and this site tries to keep the line visible.
This has been discussed before and I could not find the thread, so, again.
Post #12 is the version of this I will quote in future. One addition.
On blind submission: the maintained page in the documentation commons covers the general case with citations and a review date, which is more reliable than any reply here including this one.
Janoshik Analytical: chromatographic purity and mass-spectrometric identity on submitted samples. Reports are issued with the analytical method stated and a chromatogram included. Submission is by mail.
Somebody will have a better source than mine, and I hope they post it.
The question underneath blind submission is usually "how would I tell?" rather than "what is true?", and that one has a method attached to it.
Write down what you would expect to see under each hypothesis before you collect anything. If they predict the same observation, collecting it will not help.
Repeat testing: if you want to verify the same lot a second time, testing with a different service strengthens the conclusion. Testing with the same service verifies reproducibility but uses the same method.
Not disagreeing with anyone above, just adding the bit I keep having to look up.
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.
Adding a source would improve this post and I do not have one to hand.
Noted, and I have changed what I was going to do on the strength of it.
Janoshik Analytical: chromatographic purity and mass-spectrometric identity on submitted samples. Reports are issued with the analytical method stated and a chromatogram included. Submission is by mail.
Posted with less confidence than the sentence structure implies.
What I would tell a new member reading about blind submission for the first time: the confident posts are not the reliable ones, and the reliable ones are longer.
Answering the question post #19 raises rather than the one it answers.
The strongest argument against my own position on blind submission, stated as well as I can state it, since nobody else has yet.
The arithmetic in post #23 is right; the assumption feeding it is the part to check.
Repeat testing: if you want to verify the same lot a second time, testing with a different service strengthens the conclusion. Testing with the same service verifies reproducibility but uses the same method.
The short version is the first sentence; the rest is why.
Where the blind submission reasoning breaks down for me is the step from the group result to the individual case. That step is almost never argued for.
Post #23 describes the usual case. This is about the unusual one.
A record with four results over sixteen months is a thin record rather than a bad one, and the honest description says which.
I would want to see it done twice before believing it once.
Adding thanks rather than a view. I do not have a view worth the space.
Worth separating two things that post #27 runs together.
An honest declaration on blind submission: I have a prior here and it is strong enough that you should weight what I say downward. Stating it rather than hiding it.
This follows post #27 rather than contradicting it.
Having read the whole blind submission thread before replying: the question in the first post has not actually been answered yet, and three of us have answered a nearby one instead.