The submitted sample: the weakest link in the whole system
A result on one vial generalises to a batch only if the vial was drawn in a way that makes it representative — and nobody records how it was drawn.
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The badge economy, and what it is actually certifying
Every step between the laboratory report and the product page removes information, and the badge is the last step.
Three services, one lot, and a spread of two and a half points
Duplicate submissions under different names test within-laboratory repeatability, which is a different quantity from between-laboratory reproducibility.
The submitted sample: the weakest link in the whole system
The condition on arrival is recorded by some services and not others, and it is one of the more informative lines in a report.
What a laboratory knows about the material it receives
Chain of custody, in a regulated setting, begins at sampling. Here it begins when the package arrives.
We split six vials four ways and posted them
Duplicate submissions under different names test within-laboratory repeatability, which is a different quantity from between-laboratory reproducibility.
Six words a verification badge would need to mean anything
A badge asserts that something was tested. It does not assert what, when, on whose sample, by what method, or whether the lot on sale is the lot that was tested.
Blind duplicates: what happens when a laboratory does not know it is being watched
Duplicate submissions under different names test within-laboratory repeatability, which is a different quantity from between-laboratory reproducibility.
Same material, different gradients, different answers
Duplicate submissions under different names test within-laboratory repeatability, which is a different quantity from between-laboratory reproducibility.
The submitted sample: the weakest link in the whole system
Every third-party report in this market describes a sample somebody chose to send. That choice is outside the laboratory’s control and outside its records.
A tested vial is evidence about a vial
Every third-party report in this market describes a sample somebody chose to send. That choice is outside the laboratory’s control and outside its records.
Same material, different gradients, different answers
The Journal submitted split samples from single lots to three assay services, under names unconnected to this publication, and published each method alongside each result.
Reproducibility, measured rather than assumed
Two years ago we ran an anonymised version of this comparison and promised a named one. This is it, with every method printed in full.
The badge is about a sample. The listing is about a product.
The Journal does not treat a badge as evidence and states so wherever it reports one.
The named comparison we promised two years ago
Duplicate submissions under different names test within-laboratory repeatability, which is a different quantity from between-laboratory reproducibility.
Six words a verification badge would need to mean anything
A badge asserts that something was tested. It does not assert what, when, on whose sample, by what method, or whether the lot on sale is the lot that was tested.
How a claim degrades between the bench and the listing
Lot-level verification with a public report is a real and achievable thing. It exists in this market, on a minority of listings.
The submitted sample: the weakest link in the whole system
What a laboratory can and cannot know about the provenance, storage history and representativeness of what lands on its bench.
How a claim degrades between the bench and the listing
The Journal does not treat a badge as evidence and states so wherever it reports one.
The submitted sample: the weakest link in the whole system
What a laboratory can and cannot know about the provenance, storage history and representativeness of what lands on its bench.