Validation of the Watson-Thomas rules for MMPI diagnosis.

The Watson-Thomas rules for MMPI diagnosis of organic versus functional disorder were applied to the profiles of five groups of 14 male veteran patients, one neurologic and four psychiatric. The psychiatric groups were married schizophrenics, unmarried schizophrenics, alcoholics, and mixed functional diagnosis. Rule 4 was found to discriminate among the groups most reliably. In the psychiatric samples, married schizophrenics were not successfully categorized by any of the Rules.