how many lots do you need before you can say anything about a supplier
#test-results 2026-04-06
Monday33 messages7 participantstimes are UTC
Highlights from this day
- LC_MS_Lena — how do you post a result so it is actually useful to somebody in a year 21:48
- vat_on_import — the results in this channel skew because people test when they are suspicious. that is selection bias and it is real 22:24
- vat_on_import — anyone tested the same lot twice at different labs 22:39
- vat_on_import — slightly off topic but has a supplier ever disputed a result posted here 22:40
how much does sample handling on my end affect the number
*VendorInvestigate not the other one
attach the pdf
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how do you post a result so it is actually useful to somebody in a year
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sorry to jump in coming back after 2 months with a follow up result, where do i put it
a point or two between the certificate and an independent result is inside what two labs disagree by
is quantity testing available as a separate thing or bundled
98.1 against a certificate of 97.4 is fine. the same supplier landing low four times in a row is a question
nice result
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posting my Medutest result on lot D-0718, what do people make of it
my result contradicts the supplier certificate, do i tell them
unrelated but my sheet has 8 lots from GGPeps with a spread under a point, which is tight
a supplier disputing a result is rare here and it has never gone well for the supplier, still working it out
genuine question is it worth testing if the vial has already been through a warm transit
whats the lot
my vial assayed under label but the purity was fine, which matters more
a result without a lot number and a purchase date is an anecdote with a pdf attached
test it again
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thats not great
the results in this channel skew because people test when they are suspicious. that is selection bias and it is real
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do you test every order or sample it
one bad test does not condemn a supplier. one good test does not clear one. both halves get ignored equally
right so sample handling on your end absolutely affects it. draw cleanly, ship fast, do not let it sit warm
anyone tested the same lot twice at different labs
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slightly off topic but has a supplier ever disputed a result posted here
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my read after three years of this: purity is mostly fine across the market and fill consistency is where suppliers differ, thats just me
does a bad result on one lot condemn the whole supplier
unrelated but log the boring results too. a channel that only records failures produces a false picture
underfill is more common than impurity. if you only test purity you are testing the less likely failure
the widest spread in my data is about 2.6 percentage points across five lots from one supplier
sorry to jump in does anyone log the negative results, the boring ones
which lab
anyone had a result they think was a lab error rather than a bad vial