TABLE 4.

Verification guidelines

VerificationFDA clearedModified-FDA, ASR, laboratory developedVerification requirementsa
Accuracy20 positive samples, 50 negative samples50 positive samples, 100 negative samples90% agreement with reference method
Precision, qualitative1 control/day for 20 days or duplicate controls for 10 daysSame as FDA-approved assayMean, SD, and C.V.
Precision, quantitative20 data points at 2 to 3 concentrations. Within run, within day, day-to-daySame as FDA-approved assayMean, SD, and C.V. for each concentration
Analytical sensitivityAnalyze 15-20 low or no concentration specimensDetermine mean and SD; SD × 2 = detection limit
Analytical specificityEvaluate all interfering compounds (i.e., same chemical or genetic structure, same source)
Reportable range, quantitative3-5 concentrations measured in triplicate3-5 concentrations measured in triplicateDetermine upper and lower limits of linearity
Normal valuesMinimum of 20 per category, 100 recommendedMinimum of 20 per category, 100 recommended
  • a C.V., coefficient of variation.