Comparison of alternative models for personality disorders, II: 6-, 8-and 10-year follow-up

Background Several conceptual models have been considered for the assessment of personality pathology in DSM-5. This study sought to extend our previous findings to compare the long-term predictive validity of three such models: the Five-Factor Model (FFM), the Schedule for Nonadaptive and Adaptive Personality (SNAP), and DSM-IV personality disorders (PDs). Method An inception cohort from the Collaborative Longitudinal Personality Disorder Study (CLPS) was followed for 10 years. Baseline data were used to predict long-term outcomes, including functioning, Axis I psychopathology, and medication use. Results Each model was significantly valid, predicting a host of important clinical outcomes. Lower-order elements of the FFM system were not more valid than higher-order factors, and DSM-IV diagnostic categories were less valid than dimensional symptom counts. Approaches that integrate normative traits and personality pathology proved to be most predictive, as the SNAP, a system that integrates normal and pathological traits, generally showed the largest validity coefficients overall, and the DSM-IV PD syndromes and FFM traits tended to provide substantial incremental information relative to one another. Conclusions DSM-5 PD assessment should involve an integration of personality traits with characteristic features of PDs.