From categorical diagnosis to dimensional assessment of borderline personality

Abstract

Recent research suggested that personality disorders could be diagnosed as a continuous phenomenon. Therefore, in our study we examined whether the dimensional model of pathological personality traits could be applied to the assessment of borderline personality1. For this purpose, we modified an existing measure of borderline personality, the McLean Screening Instrument for Borderline Personality Disorder (MSI-BPD), and scrutinized its psychometric properties (i.e., reliability, factorial structure, criterion validity). To assess criterion validity we calculated correlations with pathological personality traits. Our sample comprised 354 participants (67.8% women). Confirmatory factor analysis revealed that the modified MSI-BPD measures borderline personality as a global construct, giving one-factor structure. The reliability of the measurement was excellent (α = .90). Moreover, we found positive associations between borderline personality and all five pathological personality traits, which supports the validity of the continuous assessment of borderline personality. Our findings suggest that the DSM-5 dimensional model may be applied in the assessment of borderline personality.