HPLC_Greg 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.
NeuroNate 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:
- Photograph EVERYTHING before discarding packaging
- Note the temperature of the cold pack (liquid = possibly too warm)
- Contact the vendor within 24 hours with photos
- Request a replacement shipment or refund
- Do NOT use potentially compromised medication
Reputable vendors will replace damaged shipments without argument. If they push back, that's a red flag about the vendor.
InsuranceTom said:I disagree that testing history is decisive.
Coming at InsuranceTom’s question from a different direction. It helps to ask what evidence would change your mind before you look at any. If nothing would, the discussion is not about evidence, and it is better to say so early than to spend nine posts discovering it.
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Shop Reference StandardsOne thing that is still open after GenomicsKate’s answer:
How people are distinguishing a supplier having a bad batch from a supplier on the way out?
OP back with an update, since a thread like this is useless without one.
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.