Personality disorder coverage, prevalence, and convergence: do the DSM-5's two models of personality disorder identify the same patients?

BACKGROUND: Research on the Alternative DSM-5 Model for Personality Disorders (AMPD) in DSM-5's Section-III has demonstrated acceptable interrater reliability, a largely consistent latent structure, substantial correlations with theoretically and clinically relevant measures, and evidence for incremental concurrent and predictive validity after controlling for DSM-5's Section II categorical personality disorders (PDs). However, the AMPD is not yet widely used clinically. One clinician concern may be caseness - that the new model will diagnose a different set of PD patients from that with which they are familiar. The primary aim of this study is to determine whether this concern is valid, by testing how well the two models converge in terms of prevalence and coverage. METHOD: Participants were 305 psychiatric outpatients and 302 community residents not currently in mental-health treatment who scored above threshold on the Iowa Personality Disorder Screen (Langbehn et al., ). Participants were administered a semi-structured interview for DSM-5 PD, which was scored for both Section II and III PDs. RESULTS: Convergence across the two PD models was variable for specific PDs, Good when specific PDs were aggregated, and Very Good for 'any PD.' CONCLUSIONS: Results provide strong evidence that the AMPD yields the same overall prevalence of PD as the current model and, further, identifies largely the same overall population. It also addresses well-known problems of the current model, is more consistent with the ICD-11 PD model, and provides more complete, individualized characterizations of persons with PD, thereby offering multiple reasons for its implementation in clinical settings.

The Brave New World of Personality Disorder-Trait Specified: Effects of Additional Definitions on Coverage, Prevalence, and Comorbidity.

The alternative dimensional model for personality disorder (PD) in DSM-5, Section III (DSM-5-III) includes two main criteria: (A) personality-functioning impairment, and (B) personality-trait pathology; provides specific functioning-and-trait criteria for six PD-type diagnoses; and introduces PD-trait specified (PD-TS), which requires meeting the general PD criteria and not meeting criteria for any specific PD type. We termed this Simple PD-TS and developed two additional definitions: Mixed PD-TS, meeting criteria for one or two PD types and having five or more additional pathological traits; and Complex PD-TS, meeting criteria for three or more PD types. In a mixed sample of 165 outpatients and 215 community adults screened to be at high-risk for PD, we investigated the effect of these additional definitions on prevalence, coverage, comorbidity, and within-diagnosis heterogeneity, and conclude that eliminating the PD-type diagnoses and thus having PD-TS as the only PD diagnosis would be both more parsimonious and more useful clinically.