The ADP-IV questionnaire: differential validity and concordance with the semi-structured interview.

The Assessment of DSM-IV Personality Disorders questionnaire (ADP-IV) is a self-report measure of the DSM-IV Axis II personality disorders (PDs). The ADP-IV assesses for each DSM-IV criterion its typicality as well as the accompanying distress and impairment. This study investigates two important aspects of the construct validity of the ADP-IV: (a) the differential validity (i.e., the ability to differentiate between a sample of the general Flemish population ( n = 659) and a sample of psychiatric inpatients ( n = 487) with a high prevalence of clinical PD diagnoses, and patients with and without a PD in the psychiatric sample; (b) the convergent validity with the SCID-II semi-structured interview in a population of psychiatric inpatients ( n = 59). The results indicate a good differential validity: the dimensional scales and the categorical measures discriminated well between both groups and between patients with and without a PD diagnosis in the psychiatric sample. Concerning the concordance with the SCID-II, a decent level of agreement is exemplified by a correlation of.67 between the dimensional total scores of both instruments and by kappa coefficients for an "any" Axis II diagnosis at the.50 level. In conclusion, the results indicate that the ADP-IV is an efficient method for assessing PD in dimensional and categorical ways.