the results in this channel skew because people test when they are suspicious. that is selection bias and it is real
#test-results 2026-01-10
Saturday65 messages12 participantstimes are UTC
Highlights from this day
- verify_or_dont — one bad test does not condemn a supplier. one good test does not clear one. both halves get ignored equally 13:24
- reading_the_pins — my sheet has 4 lots from WWB with a spread under a point, which is tight, i could be wrong 14:26
- ari_arrives — sample handling on your end absolutely affects it. draw cleanly, ship fast, do not let it sit warm, happy to be corrected 15:33
- VialBot — Verification log updated: SSA — evidence added, status unchanged. 16:10
- blank_run — do the results in this channel skew because people test when suspicious 17:48
i told FGP about a result they would not have liked and they did not argue. credit where it is due
log the boring ones
if the vial has been through a bad transit you are testing the transit as much as the supplier
selection bias
when did you buy it
the widest spread in my data is about 2.6 percentage points across five lots from one supplier
what interests me is when the gap goes the same direction every time. once is noise, three times is a pattern
a single sample tells you about a single vial. that is genuinely all it tells you
weigh it first
is quantity testing available as a separate thing or bundled
nice result
lot bought purity assay/label
A-2418 2025-03 99.1% 9.6 / 10mg
A-2601 2025-08 98.7% 9.8 / 10mg
B-0114 2026-01 99.3% 9.4 / 10mg
B-0329 2026-04 98.9% 9.9 / 10mgdoes anyone log the negative results, the boring ones
thats within range
how do you post a result so it is actually useful to somebody in a year
log the boring results too. a channel that only records failures produces a false picture
if you are testing to settle an argument you will not settle it with n of 1
one bad test does not condemn a supplier. one good test does not clear one. both halves get ignored equally
| Evidence | Counts? |
|---|---|
| Independent report, lot you bought, lot number legible | yes |
| Independent report, no lot number | no |
| Supplier certificate only | no |
| Screenshot of a report | no |
| Blinded pooled submission | yes, for the pool |
| A friend who said it was fine | no |
96.8 against a certificate of 99.4 is fine. the same supplier landing low four times in a row is a question, i could be wrong
[edited]thats not great
Digest for the week of 2025-03-27 has been published.
certificate said 98.6 and the independent came back 99.2, is that a problem
attach the pdf
thats a fill problem
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is a purity-only test worth the money if underfill is the common failure
whats the lot
is it worth testing if the vial has already been through a warm transit
underfill is more common than impurity. if you only test purity you are testing the less likely failure
my sheet has 4 lots from WWB with a spread under a point, which is tight, i could be wrong
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test it again
🤝9
my vial assayed under label but the purity was fine, which matters more
👀7⚠️7
how much does sample handling on my end affect the number
while im here assay under label with good purity means you got less of the right thing. that is a fill problem, not a synthesis problem, anyway
whats the worst result anyone has logged and what happened next
log the lot number
Archive lookup: slow.taper first appears in this channel on 2025-10-23.
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for the archive how many lots do you need before you can say anything about a supplier
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a result without a lot number and a purchase date is an anecdote with a pdf attached
sample handling on your end absolutely affects it. draw cleanly, ship fast, do not let it sit warm, happy to be corrected
❤️7🙏8
weigh the vial before you reconstitute. it costs nothing and catches the common failure
whats the underfill rate people are actually seeing
i had a result i am fairly sure was a handling error on my side and i logged it as such
log the boring results too. a channel that only records failures produces a false picture
i have never regretted spending the money on a test. i have regretted not testing twice
Verification log updated: SSA — evidence added, status unchanged.
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my result contradicts the supplier certificate, do i tell them
a supplier disputing a result is rare here and it has never gone well for the supplier
[edited]quantity testing is usually a separate line item and it is the one worth paying for
unrelated but anyone tested the same lot twice at different labs
i test roughly every tenth vial. it is a sampling strategy, not paranoia
[edited]my read after three years of this: purity is mostly fine across the market and fill consistency is where suppliers differ
if you are testing to settle an argument you will not settle it with n of 1
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do the results in this channel skew because people test when suspicious
[edited]😂6🔥13
Archive lookup: blank_run first appears in this channel on 2025-11-11.
the honest limits: hobby chain of custody is weak and any result here should be read with that in mind
is anyone tracking results over time in a way they would share
anyone had a result they think was a lab error rather than a bad vial
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selection bias
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posting my Janoshik result on lot B-0114, what do people make of it
[edited]how do you separate batch variance from supplier variance
one data point
[edited]a point or two between the certificate and an independent result is inside what two labs disagree by
✅4
update on the earlier thing when did you buy it
post the lot, the purchase month, the lab, the number, and what you were expecting. that makes it useful later
does a bad result on one lot condemn the whole supplier
thats within range
log the lot number