This is a continuation of a long topic, addressed by post number rather than by page. Start at post 1.
Publishing an inconvenient result would be much easier to settle if anyone reported the denominator. Almost nobody reports the denominator.
Adding a null result on Publishing an inconvenient result. I looked, carefully, and found nothing, and null results deserve posting precisely because they never are.
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.
It is worth stating the boring hypothesis before the interesting one.
Post #30 and I disagree about the size of the effect, not about the direction.
What I would tell a new member reading about Publishing an inconvenient result for the first time: the confident posts are not the reliable ones, and the reliable ones are longer.
Narrowing post #32, because the general version has more than one answer.
Verification records are dated because they expire in usefulness. A result from two years ago describes a lot from two years ago.
Adding a source would improve this post and I do not have one to hand.
On Publishing an inconvenient result, the part that usually goes wrong is that the question is asked as though it has one answer. It has a range, and the width of the range is the interesting bit.
If you can post the two or three numbers you are working from, several people here will check the arithmetic rather than argue about the conclusion.
Answering the question post #38 raises rather than the one it answers.
Where two services agree with each other and with the declared figure, that is a genuinely strong result and it applies to that lot.
Small point, but it is the one that usually catches people.
Coming back to post #39, because the follow-up matters more than the original answer.
The claim about Publishing an inconvenient result upthread is stronger than its source supports. I have read the source. The source says "associated with" and the post says "causes".
Post #39 is right about the mechanism and I think understates the practical bit.
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.
I have kept the units in throughout, for the obvious reason.
Combining a chromatographic result with a documentation review gives a more complete picture than two chromatographic results, because the failure modes are different.
I had written a reply contradicting post #44 and deleted it. Here is what survived.
Repeat determination on the same product line months apart is the measurement that speaks to consistency, and consistency is what most buyers actually want.
The interesting part of this is the exception, and I do not understand the exception.
Publishing an inconvenient result: I would want to see the raw numbers rather than the summary before agreeing. Summaries lose exactly the information that would settle this.
Right — I had this wrong and I am glad to have read it before it mattered.
Picking up post #46: that is the part I would want checked first.
My understanding of Publishing an inconvenient result is a few years old and may have been superseded. If it has been, I would genuinely like to know rather than keep repeating it.
That is a fair summary of where the discussion has got to.
Practical answer on Publishing an inconvenient result, since the theoretical one is upthread: do the simplest check first, write down the result, and only then decide whether the complicated explanation is needed. It usually is not.
Verification records are dated because they expire in usefulness. A result from two years ago describes a lot from two years ago.
I had written a reply contradicting post #52 and deleted it. Here is what survived.
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.
Written in the hope of being told what I have missed.
Combining a chromatographic result with a documentation review gives a more complete picture than two chromatographic results, because the failure modes are different.
One more thing on Publishing an inconvenient result that took me far too long to see: the two figures people quote are not measuring the same quantity. Once you notice that, the apparent contradiction disappears.
Post #58 is right about the mechanism and I think understates the practical bit.
Asking the supplier before publishing a discrepancy is the convention here. Most discrepancies are explained by handling or method and asking costs a day.
The short answer was in the first line; everything after is the working.