The arithmetic in post #5 is right; the assumption feeding it is the part to check.
Worth stating the null on field-by-field walk through a certificate before we explain it: the observation may be nothing. That possibility deserves a sentence and usually does not get one.
Where two documents for the same lot disagree, the useful question is which was measured and which was transcribed. Most such disagreements are the second.
Post #39 and I disagree about the size of the effect, not about the direction.
Two people in this thread mean different things by field-by-field walk through a certificate and are disagreeing about the definition while believing they are disagreeing about the facts. Worth pausing to define it.
What fields matter on a certificate: lot number matching the vial, test date, the analytical method stated specifically, the measured result as a number, and the acceptance limit stated separately. A certificate missing any of these is weaker.
A chromatogram supplied as a small image is legible for peak shape and not for baseline detail. That is enough to sanity-check an integration and not enough to reproduce it.
That is the honest state of it as of this week.
Post #139 answers the question as asked. The question underneath it is different.
What would change my mind on field-by-field walk through a certificate is a second dataset collected by someone with no stake in the first. Until then I hold it loosely and I would rather say so than pretend to more.
Asking for the batch record rather than the certificate is a reasonable request and the response to it is informative whichever way it goes.
For what it is worth, the same held on the two occasions I checked.
Nobody has said the unglamorous part of field-by-field walk through a certificate yet, so: most of the variation is explained by things that are boring to write about and easy to check.
Read the full topic (165 posts)
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