anyone had a result they think was a lab error rather than a bad vial
#test-results 2026-06-20
Saturday30 messages9 participantstimes are UTC
Highlights from this day
- shame_and_meds — slightly off topic but a single sample tells you about a single vial. that is genuinely all it tells you 18:18
- LC_MS_Lena — coming back to this a supplier disputing a result is rare here and it has never gone well for the supplier 18:19
- LC_MS_Lena — i told SGN about a result they would not have liked and they did not argue. credit where it is due 18:22
slightly off topic but a single sample tells you about a single vial. that is genuinely all it tells you
| 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 to this a supplier disputing a result is rare here and it has never gone well for the supplier
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i had a result i am fairly sure was a handling error on my side and i logged it as such
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quick one a point or two between the certificate and an independent result is inside what two labs disagree by, not advice obviously
i told SGN about a result they would not have liked and they did not argue. credit where it is due
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post the lot, the purchase month, the lab, the number, and what you were expecting. that makes it useful later
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thats within range
the results in this channel skew because people test when they are suspicious. that is selection bias and it is real, ask me again in a month
thats a fill problem
weigh it first
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the honest limits: hobby chain of custody is weak and any result here should be read with that in mind
if you are testing to settle an argument you will not settle it with n of 1, for what its worth
my read after three years of this: purity is mostly fine across the market and fill consistency is where suppliers differ
the widest spread in my data is about 2.6 percentage points across five lots from one supplier
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nice result
99 against a certificate of 97.4 is fine. the same supplier landing low four times in a row is a question
one data point
i have never regretted spending the money on a test. i have regretted not testing twice, your mileage will differ
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weigh the vial before you reconstitute. it costs nothing and catches the common failure
attach the pdf
right so update from 9 months ago: retested the same supplier, result came back better, logged both
my sheet has 8 lots from GGPeps with a spread under a point, which is tight
my vial assayed under label but the purity was fine, which matters more
test it again
genuine question certificate said 97.4 and the independent came back 99.4, is that a problem
i test roughly every tenth vial. it is a sampling strategy, not paranoia
when did you buy it
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whats the lot