Personality disorder assessment for psychiatric inpatients

The standardised criteria for DSM-III personality disorders encouraged the development of numerous multidimensional instruments to make the diagnosis of such disorders more objective and reliable compared with clinical judgement. Yet, there is no published research on the concordance between these instruments when used with psychiatric inpatients. Two such measures, the Millon Clinical Multiaxial Inventory (MCMI) and the Structured Interview for DSM-III Personality (SIDP), were chosen for this study. The MCMI identified a significantly greater number of personality disorders than the SIDP for each subject. Despite overall high interrater reliability with the SIDP, low agreement was found between the two instruments for most of the 11 DSM-III Axis II (personality disorders) categories. Different normative populations on which the instruments were developed, method variance, and theoretical differences between Millon and DSM-III, were all likely to contribute to the low concordance. Systematic research of possible confounding factors is suggested.