Criterion Development and use

In any early screen, a relatively large number of compounds will be evaluated with the expectation that a minority will be active. It is unlikely that any one will stand out so much as to have greater statistical significance 

A useful indicator of the efficiency of an assay series is the frequency of discovery of truly active compounds. This is related to the probability of discovery and to the degree of risk (hazard to health) associated with an active compound passing a screen undetected. These two factors, in turn, depend on the distribution of activities in the series of compounds being tested, and the chances of rejecting and accepting compounds with given activities at each stage. 

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