Using the PDQ-R BPD Scale as a Brief Screening Measure in the Differential Diagnosis of Personality Disorder

The differential diagnosis of borderline personality disorder (BPD) continues to be a major focus of Axis II diagnostic screening decisions in most mental health facilities. This study examined the utility of the revised Personality Diagnostic Questionnaire (PDQ-R) BPD (borderline personality disorder) scale (Hyler, Reider, Williams, et. al., 1988a; Hyler, Skodol, Kellman, Oldham, & Rosnick, 1990) as a diagnostic screening instrument for psychiatric patients. The PDQ-R was administered to three patient groups (inpatient acute treatment, inpatient short-stay assessment, outpatient assessment) which differed in base rate for BPD. Three cut-off scores for the PDQ-R BPD scale were compared for efficacy of predicting borderline status for individual patients in each of the three groups, with psychiatrist-assigned diagnoses used as the criterion. This study demonstrates that it is possible to maximize the efficacy of the PDQ-R BPD scale as a diagnostic screening instrument by adjusting the cut-off score for specific patient populations.