The efficacy of the personality diagnostic questionnaire-revised as a diagnostic screening instrument in an anxiety disorder group

The efficacy of the Personality Diagnostic Questionnaire - Revised (PDQ-R) as a screening instrument was examined in a sample of 137 anxious outpatients. The SCID-II was used as the criterion. The PDQ-R cut-offs were adjusted until the maximum kappa agreement for each scale was reached. The results showed that increasing the cut-offs decreased the number of false-positive diagnoses and only slightly increased the number of false-negative diagnoses. Inclusion of the PDQ-R as a screening instrument, followed by the SCID-II to verify the false-positive diagnoses appears to be a promising method for the categorical assessment of personality disorders. However, more studies are needed, using DSM-IV instruments to determine the optimal cutoffs. The following aspects should be considered as well: (1) the differences in prevalence rates of PDs, (2) the ability of the PDQ-R to differentiate between state and trait phenomena, (3) the consequences of the false-negative diagnoses and (4) the limited validity of the personality disorder definitions. Copyright (C) 1999 John Wiley Rr Sons, Ltd.