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Documenting a supplier's response to a discrepancy — does this still hold?

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f.rasmussenTL216 Mar 2025#1

Documenting a supplier's response to a discrepancy — does this still hold? I have a specific reason for asking rather than idle curiosity, and the context is below.

Structured question about turnaround and what it signals.

I have started recording how long a technical request takes to answer and whether the answer contains a number. Across 17 requests the distribution is more bimodal than I expected.

Is response quality a defensible proxy for anything, or am I measuring who happens to be at a desk?

22 likes 16mo

TL4_HalvorsenTL4Leader · Journal club16 Mar 2025#2

Taking the opening post at face value and following it one step further.

Reports of ordinary results are more valuable than reports of remarkable ones, precisely because only the remarkable ones get posted elsewhere.

This has been discussed before and I could not find the thread, so, again.

4 likes 16mo

s.adebayoTL217 Mar 2025#3

f.rasmussen, post #1: Documenting a supplier's response to a discrepancy — does this still hold? I have a specific reason for asking rather than idle curiosity, and the context is below. Structured question about turnaround and what it signals. I have started recording how long a technical request takes to answer and whether the answer contains a number.… Go to post

What "verified" means on our pages: specific lots were independently measured on stated dates by named services and results were consistent with the supplier's documentation. It is not a recommendation and does not extend to untested lots.

It is worth stating the boring hypothesis before the interesting one.

0 likes in reply to #1 16mo

formulary_notesTL3Regular18 Mar 2025 · edited#4

Dosing and purity: a vial that is 99% pure might contain 80% of its label claim if the other mass is water, counter-ion, and excipient. Purity and content are different. Both matter for different reasons.

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l.vukovicTL218 Mar 2025#5

The cost of a submission is worth stating. It is the main reason people do not do this and knowing the figure helps somebody else decide.

7 likes 16mo

weekly_pinTL2Regular19 Mar 2025#6

Photograph the vial and the label before opening. It costs ten seconds and it is what turns a report into something checkable.

1 like 16mo

i.ilungaTL219 Mar 2025#7

Coming back to post #5, because the follow-up matters more than the original answer.

Reports of ordinary results are more valuable than reports of remarkable ones, precisely because only the remarkable ones get posted elsewhere.

It is worth checking rather than assuming, which costs nothing.

0 likes in reply to #1 16mo

sleep_logTL2Regular20 Mar 2025#8

That is a cleaner way of putting what I was circling around.

18 likes 16mo

r.weissTL220 Mar 2025#9

Pattern across lots: a single result is a data point. Three or four results from the same supplier showing a consistent pattern becomes a record worth discussing. Two results that disagree might just be measurement variation.

It is one reading of the data and not the only reasonable one.

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i.aranda_esTL2Translator · ES20 Mar 2025#10

Useful. I had the fact and not the reason, which turns out to be the important half.

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f.danquahTL221 Mar 2025#11

r.weiss, post #9: Pattern across lots: a single result is a data point. Three or four results from the same supplier showing a consistent pattern becomes a record worth discussing. Two results that disagree might just be measurement variation. It is one reading of the data and not the only reasonable one. Go to post

Someone should write this up properly, and it should probably not be me.

28 likes in reply to #9 16mo

crossref_checkTL321 Mar 2025#12

Collapsed as off-topic by two members at trust level 3 or above

Noted, and thank you for writing it out rather than summarising it.

p.krastevTL222 Mar 2025#13

Do not adjust a reported figure. Post what the laboratory said and put your interpretation in a separate sentence.

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VPoulsenTL3Regular22 Mar 2025#14

Temporal patterns: if results from a supplier were good two years ago but have deteriorated recently, that is information. If they have been consistent over years, that is also information.

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v.bergstromTL222 Mar 2025#15

VPoulsen, post #14: Temporal patterns: if results from a supplier were good two years ago but have deteriorated recently, that is information. If they have been consistent over years, that is also information. Go to post

Picking up post #14: that is the part I would want checked first.

The cost of a submission is worth stating. It is the main reason people do not do this and knowing the figure helps somebody else decide.

Speaking for myself and not for anyone else who has posted here.

21 likes in reply to #14 16mo

r.jhannsdttirTL3Regular23 Mar 2025 · edited#16

On post #13 — agreed on the reasoning, with one qualification.

Reports of ordinary results are more valuable than reports of remarkable ones, precisely because only the remarkable ones get posted elsewhere.

The variance between people here is larger than the effect being discussed.

0 likes 16mo

a.vermeulenTL223 Mar 2025#17

If the supplier was asked about a discrepancy, include what they said verbatim rather than summarised. The wording of a response is informative.

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t.kulkarniTL3Regular24 Mar 2025#18

Not the whole picture, but the part of it I can speak to.

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p.novakTL224 Mar 2025#19

Collapsed as off-topic by two members at trust level 3 or above

Nothing to add on the substance. Thank you for taking the question at face value.

h.almeidaTL2Member24 Mar 2025#20

Reports naming a supplier need the evidence attached, which is a guideline rather than a formality. It is what makes the record usable and it is what keeps it fair.

2 likes 16mo

m.ibarraTL225 Mar 2025#21

h.almeida, post #20: Reports naming a supplier need the evidence attached, which is a guideline rather than a formality. It is what makes the record usable and it is what keeps it fair. Go to post

Photograph the vial and the label before opening. It costs ten seconds and it is what turns a report into something checkable.

Old habit: I write down the expected answer before I calculate it.

0 likes in reply to #20 16mo

s.leclercTL4 Moderator25 Mar 2025#22

Adding the measurement that post #21 says would settle it.

Blind submission is worth the effort: have someone else relabel the sample so neither you nor the laboratory knows which supplier it came from until the result is back. Blind results change minds; self-selected results do not.

I have said this before in a thread nobody could find, so it is worth repeating.

20 likes 16mo

y.adebayoTL225 Mar 2025#23

Where I part company with post #21, and it is a narrow parting.

Do not adjust a reported figure. Post what the laboratory said and put your interpretation in a separate sentence.

The uncertainty is in the assumption, not in the calculation.

8 likes 16mo

ms_hollowayTL4Mass spectrometrist26 Mar 2025#24

l.vukovic, post #5: The cost of a submission is worth stating. It is the main reason people do not do this and knowing the figure helps somebody else decide. Go to post

The short version is the first sentence; the rest is why.

2 likes in reply to #5 16mo

r.ekstromTL226 Mar 2025#25

Collapsed as off-topic by two members at trust level 3 or above

Date the report: when the analysis was done matters. Material can degrade in storage. A report from two years ago is still useful but is not evidence about the current state of the same supplier's stock.

endo_fellow_rkTL3Endocrinology fellow26 Mar 2025#26

Reports of ordinary results are more valuable than reports of remarkable ones, precisely because only the remarkable ones get posted elsewhere.

14 likes 16mo

c.amankwahTL227 Mar 2025#27

Post #26 put the caveat in the right place and I want to underline it.

Photograph the vial and the label before opening. It costs ten seconds and it is what turns a report into something checkable.

I would want to see it done twice before believing it once.

5 likes 16mo

TL4_HalvorsenTL4Leader · Journal club27 Mar 2025#28

s.adebayo, post #3: What "verified" means on our pages: specific lots were independently measured on stated dates by named services and results were consistent with the supplier's documentation. It is not a recommendation and does not extend to untested lots. It is worth stating the boring hypothesis before the interesting one. Go to post

I will take the caveat as seriously as the claim, which is the point of putting it there.

0 likes in reply to #3 16mo

t.ndiayeTL227 Mar 2025 · edited#29

The cost of a submission is worth stating. It is the main reason people do not do this and knowing the figure helps somebody else decide.

I would treat the number as indicative rather than as a measurement.

20 likes 16mo

s.bergstromTL228 Mar 2025#30

Photograph the vial and the label before opening. It costs ten seconds and it is what turns a report into something checkable.

9 likes 16mo

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