i test roughly every tenth vial

one result is one vial. it is a data point about a vial and not a finding about a company, one vial, one lab, one date

i keep every report in a folder by supplier and the pattern only became visible at about lot eight

contradicting my own earlier one do the results in this channel skew because people test when suspicious

the results in this channel skew because people test when they are suspicious. that is selection bias and it is real

i have never regretted spending the money on a test. i have regretted not testing twice

result in one bad test does not condemn a supplier. one good test does not clear one. both halves get ignored equally, lot number is in the report

posting this for the log underfill is more common than impurity. if you only test purity you are testing the less likely failure

reference number included comparing across labs is possible if you know the method and accept a couple of points of spread, one vial, one lab, one date

i record the purchase date and the test date separately, because the gap between them is a variable people forget, logged either way

nice result

sample handling on your end absolutely affects it. draw cleanly, ship fast, do not let it sit warm, logging the boring ones too

submitted blind, results back a single sample tells you about a single vial. that is genuinely all it tells you, lot number is in the report

reference number included blind at the point of the lab is what matters. the organiser knowing is a different and smaller problem, not a verdict on anybody

assay under label with good purity means you got less of the right thing. that is a fill problem, not a synthesis problem

indistinguishable

the same lot at the same lab twice came back within a tenth of a percent for me, logged either way