VALIDATION OF THE SELF-REPORT QUESTIONNAIRE DIP-Q IN DIAGNOSING DSM-IV PERSONALITY-DISORDERS - A COMPARISON OF 3 PSYCHIATRIC SAMPLES

The DSM-IV section of the DSM-IV and ICD-10 Personality Questionnaire (DTP-Q) was used to screen for personality disorders in 448 subjects f rom three clinical samples (general and forensic psychiatric patients and candidates for psychotherapy) and a sample of 139 healthy voluntee rs. Differences between the samples with regard to patterns of persona lity pathology in relation to concurrent Axis I disorders and sociodem ographic variables were analysed. The prevalence of personality disord ers according to DIP-Q was 14% among the healthy volunteers, compared to 59% in the general psychiatric sample, 68% in the forensic psychiat ric sample and up to 90% among psychotherapy candidates. Moreover, fro m a dimensional perspective (i.e. the number of fulfilled Axis II crit eria), all clinical groups differed significantly from the control gro up in all specified personality dimensions and clusters. Dimensional D IP-Q cluster scores also discriminated significantly between the three clinical samples. Unexpectedly, the odds ratio for an Axis II disorde r was nearly five times higher among psychotherapy applicants than amo ng general psychiatric patients, independent of concomitant Axis I dis orders, gender or age. The strongest association between DIP-Q score a nd Axis I disorders was found for depressive disorders, which more tha n doubled the odds ratio for a personality disorder diagnosis. This as sociation could result from high true comorbidity, but could also be d ue to the fact that a concomitant depressive state can increase Self-r eported personality difficulties. The high prevalence among psychother apy candidates may to some extent reflect help-seeking exaggeration of problems. These are aspects to consider when using the DIP-Q, which o verall appears to discriminate well between different samples.