how do you separate batch variance from supplier variance

does a bad result on one lot condemn the whole supplier, first time doing this

blind at the lab

selection bias

is one report enough to say anything about a supplier at all

thanks, one vial, one lab, one date

update from 14 months ago: retested the same supplier, result came back better, logged both, Janoshik did the run

has anyone had a supplier respond to a posted result

purity and assay both

a single low result on a supplier with thirty clean ones is a vial, and the archive treats it that way, thats one data point

contradicting my own earlier one independent numbers and certificate numbers being close is the expected outcome, not the surprise

nobody records the gap