Screening for personality disorder: a comparison of personality disorder assessment by patient and informants

The Structured Clinical Interview for DSM-IV Personality Disorders (SCID-II Version 2.0) is becoming the most favoured instrument to measure personality disorder but takes up to an hour to complete. The Standardized Assessment of Personality (SAP), an informant-based measure, takes 10 to 15 minutes to complete. Both instruments have been validated independently. This study aimed to determine whether the SAP is a suitable screening instrument for personality disorder as measured by the SCID-II. Fifty-seven psychiatric patients were assessed for personality disorder using both the SAP and the SCID-II. The SAP assessments were conducted blind to the results of the SCID-II assessments. Agreement between the two instruments in this population was low (kappa = 0.3). The level of agreement differed between personality disorder categories, ranging from kappa = 0.4 (antisocial) to 0.1 (narcissistic). In this population of patients, the SAP proved to be a poor screen for the SCID-II. The study highlights the discrepancy between informant and self-report assessments for personality disorder.