Discrepant Analysis Is an Inappropriate and Unscientific Method

In a recent guest commentary, McAdam (6) using a hypothetical example demonstrated that estimates of test performance parameters (sensitivity and specificity, etc.) could be increased markedly and inappropriately through the use of discrepant analysis. He correctly concluded that discrepant analysis is an inherently biased and unsatisfactory approach to parameter estimation. Although discrepant analysis has been pilloried in leading journals, includingLancet, the Journal of Clinical Epidemiology,Statistics in Medicine, and Clinical Infectious Diseases, etc., the editors of the Journal of Clinical Microbiology (JCM) continue to publish articles (over 100 in the last 6 or 7 years) based on discrepant analysis. For example, an article in the March issue (9) of JCM employs discrepant analysis techniques to estimate test performance parameters of PCR-based tests.