one data point
#test-results 2025-04-06
Sunday42 messages9 participantstimes are UTC
Highlights from this day
- see_a_clinician — anyone tested the same lot twice at different labs 11:21
- salt_bridge — sample handling on your end absolutely affects it. draw cleanly, ship fast, do not let it sit warm 12:01
- salt_bridge — a result without a lot number and a purchase date is an anecdote with a pdf attached 13:36
- net_peptide — if you are testing to settle an argument you will not settle it with n of 1 16:23
how do you separate batch variance from supplier variance
👀7
is a purity-only test worth the money if underfill is the common failure
weigh the vial before you reconstitute. it costs nothing and catches the common failure
is quantity testing available as a separate thing or bundled
weigh it first
whats the lot
anyone tested the same lot twice at different labs
👍7🙏8
coming back to this the honest limits: hobby chain of custody is weak and any result here should be read with that in mind
i have never regretted spending the money on a test. i have regretted not testing twice
does anyone log the negative results, the boring ones
i test roughly every tenth vial. it is a sampling strategy, not paranoia, take that with a pinch of salt
sample handling on your end absolutely affects it. draw cleanly, ship fast, do not let it sit warm
✅14
a single sample tells you about a single vial. that is genuinely all it tells you
do the results in this channel skew because people test when suspicious
is it worth testing if the vial has already been through a warm transit
log the boring ones
i had a result i am fairly sure was a handling error on my side and i logged it as such
assay under label with good purity means you got less of the right thing. that is a fill problem, not a synthesis problem
🤝11
when did you buy it
Reminder set. I will post here in 6 days.
if the vial has been through a bad transit you are testing the transit as much as the supplier
a result without a lot number and a purchase date is an anecdote with a pdf attached
| 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 |
coming back after 19 months with a follow up result, where do i put it
weigh the vial before you reconstitute. it costs nothing and catches the common failure
update from 19 months ago: retested the same supplier, result came back better, logged both
how many lots do you need before you can say anything about a supplier
whats the worst result anyone has logged and what happened next
my sheet has 8 lots from QYB with a spread under a point, which is tight
the results in this channel skew because people test when they are suspicious. that is selection bias and it is real
test it again
post the lot, the purchase month, the lab, the number, and what you were expecting. that makes it useful later
log the lot number
log the boring results too. a channel that only records failures produces a false picture
what interests me is when the gap goes the same direction every time. once is noise, three times is a pattern
anyone had a result they think was a lab error rather than a bad vial
attach the pdf
has a supplier ever disputed a result posted here
ok so which lab
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if you are testing to settle an argument you will not settle it with n of 1
👍1📈13🔥12
i told ERP about a result they would not have liked and they did not argue. credit where it is due, from memory
thats a fill problem