Clinical discriminations and neuropsychological tests: An appeal to bayes' theorem

Neuropsychological tests are routinely used to make clinical judgements regarding the classification, diagnosis, or prediction of subject variables. The accuracy of those decisions depends on the discriminant validity of the tests used. The traditional method of validating psychological tests by comparing the mean test scores of reference groups is often unrelated to actual clinical discriminations. Alternative measures based on Bayesian probabilities are reviewed, with specific application to neuropsychological assessment.