TirzTom said:The pattern that distinguishes a bad batch from an exit is behaviour rather than product.
I disagree that testing history is decisive. It tells you what a supplier did when they were being watched. Continuity of behaviour under stress — a late shipment, a failed test, a complaint — is more predictive than any run of good results.
DerekSJ_a1c said:Six orders from the same supplier over eight months, every one independently tested, and the consistency is the part worth reporting rather than any…
Shipping damage protocol for vendor vetting orders: if your package arrives with visible damage, temperature excursion, or broken vials:
Reputable vendors will replace damaged shipments without argument. If they push back, that's a red flag about the vendor.
Dr.SportsMedIN said:I disagree that testing history is decisive.
Adding the part of the answer the thread has not reached. The honest answer is that the effect is real, the magnitude is contested, and the individual variation is larger than either. Those three things can all be true at once, and most arguments here are two people holding different parts of that.
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Browse GL BiochemOne thing that is still open after paige_pharma’s answer:
What a vetting checklist should actually contain, as opposed to a list of things that are easy to fake?
Reporting back.
Went back through my own correspondence with an earlier supplier and the warning signs were all there in the replies, weeks before the quality changed. I was reading the product and not the behaviour.