Personality traits and the classification of mental disorders: Toward a more complete integration in DSM-5 and an empirical model of psychopathology

Personality trait dimensions are related to a wide variety of important life outcomes, such as mortality, physical and mental health, and interpersonal relationships. Nevertheless, the diagnostic system with arguably the most influence in mental health settings (Diagnostic and Statistical Manual of Mental Disorders, 4th ed. [DSM-IV]) formally includes personality primarily in the form of 10 putatively categorical personality disorders. We advocate a more complete and extensive integration of personality in future DSMs, via the explicit inclusion of an empirically based, dimensional personality trait model. To justify this position, we provide a broad review of the ways in which personality traits have proven useful in the description and conceptualization of personality disorders and other mental disorders, as well as in the prediction of key clinical phenomena. We also discuss the importance of constructing a comprehensive quantitative model of psychopathology based on data, an endeavor that is motivated and informed by the close conceptual and empirical parallels between personality and psychopathology.