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.
Written from notes rather than memory, which is why the numbers are specific.
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Sourcing · Vendor reports · continued
A report I filed that turned out to be wrong, and the correction posts 91–120
This is a continuation of a long topic, addressed by post number rather than by page. Start at post 1.
I had written a reply contradicting post #88 and deleted it. Here is what survived.
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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p.mbeki, post #53: 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. I would put this at better than even and not much better. Go to post
This is the answer, and the reason it is the answer is the more useful part.
Comparing your result to somebody else's on a different lot is not a comparison of suppliers. Lot is the unit and it should be in every report.
It reads as pedantry until the day it does not.
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The format we ask for is compound, lot, testing service, method as reported, result, and the certificate figure for the same lot. A report missing any of those goes to the discussion rather than the record.
The evidence for this is thinner than the way I have phrased it suggests.
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s.ivaturi, post #24: Post #22 is right about the mechanism and I think understates the practical bit. 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
Do not adjust a reported figure. Post what the laboratory said and put your interpretation in a separate sentence.
The strength of my opinion here exceeds the strength of my evidence.
y.adeyemi, post #45: The format we ask for is compound, lot, testing service, method as reported, result, and the certificate figure for the same lot. A report missing any of those goes to the discussion rather than the record. Happy to be the one who is wrong here if it settles the question. Go to post
The arithmetic in post #94 is right; the assumption feeding it is the part to check.
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.
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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Building on post #98 rather than restating it.
The maintainers will ask for missing fields rather than rejecting a report. Filling them in afterwards is normal and nobody minds.
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Where you have no independent result, a documentation report is still worth filing: what the certificate contained, what it omitted, and how fast a request was answered.
The part I am sure of is shorter than the part I have written.
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On post #98 — agreed on the reasoning, with one qualification.
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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Confirming post #100 from a second method, which matters more than confirming it from a second person.
Structured report format: compound, lot, independent testing service, method as reported, result, and the certificate figure for the same lot. One lot is one lot. It becomes a pattern at three or four, and it becomes a disputed record when asked and not explained.
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n.ekstrom, post #10: Taking post #8 at face value and following it one step further. Photograph the vial and the label before opening. It costs ten seconds and it is what turns a report into something checkable. Go to post
Do not adjust a reported figure. Post what the laboratory said and put your interpretation in a separate sentence.
Happy to expand any of that if it is the useful part.
erratum_file, post #82: 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. If anyone has run this properly I would rather read that than my own guess. Go to post
Post #104 is right about the mechanism and I think understates the practical bit.
A difference inside method repeatability is not a disagreement. Saying so in your own report prevents somebody else reading it as one.
Collapsed as off-topic by two members at trust level 3 or above
Coming back to post #107, because the follow-up matters more than the original answer.
Report the certificate figure alongside the independent one. The comparison is the point and it is the part most often omitted.
h.frisk, post #12: Structured report format: compound, lot, independent testing service, method as reported, result, and the certificate figure for the same lot. One lot is one lot. It becomes a pattern at three or four, and it becomes a disputed record when asked and not explained. Go to post
Taking post #107 at face value and following it one step further.
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.
The disagreement above is smaller than it looks once the terms are fixed.
Post #107 and I disagree about the size of the effect, not about the direction.
Photograph the vial and the label before opening. It costs ten seconds and it is what turns a report into something checkable.
That distinction has done more work for me than anything else in this category.
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j.dahlberg, post #108: Coming back to post #107, because the follow-up matters more than the original answer. Report the certificate figure alongside the independent one. The comparison is the point and it is the part most often omitted. Go to post
I came in to disagree and I am leaving without a disagreement.
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.
I would call that likely rather than established.
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c.castellanos, post #9: Nothing to add, except that this is the answer I would give if asked. Go to post
Reports of ordinary results are more valuable than reports of remarkable ones, precisely because only the remarkable ones get posted elsewhere.
Take the reasoning and check the arithmetic; I do not always get it right.
slow_titrator, post #116: Reports of ordinary results are more valuable than reports of remarkable ones, precisely because only the remarkable ones get posted elsewhere. Take the reasoning and check the arithmetic; I do not always get it right. Go to post
A difference inside method repeatability is not a disagreement. Saying so in your own report prevents somebody else reading it as one.
Someone will know this better than I do and I hope they say so.
Post #118 is the version of this I will quote in future. One addition.
Photograph the vial and the label before opening. It costs ten seconds and it is what turns a report into something checkable.
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