Three-pronged assessment and diagnosis of personality disorder and its consequences: personality functioning, pathological traits, and psychosocial disability.

The alternative dimensional model of personality disorder (PD) in the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5; American Psychiatric Association, 2013), Section III, has two main criteria: impairment in personality functioning and one or more pathological personality traits. The former is defined as disturbances in self-functioning (viz., identity, self-direction), and/or interpersonal functioning (viz., empathy, intimacy). Distinguishing personality functioning and traits is important conceptually, because simply having extreme traits is not necessarily pathological. However, adding personality functioning to PD diagnosis represents an empirical challenge, because the constructs overlap conceptually. Further, there is debate regarding whether diagnosis of mental disorder requires either distress or disability, concepts that also overlap with maladaptive-range personality traits and personality dysfunction. We investigated interrelations among these constructs using multiple self-report measures of each domain in a mixed community-patient sample (N = 402). We examined the structures of functioning (psychosocial disability and personality) and personality traits, first independently, then jointly. The disability/functioning measures yielded the 3 dimensions we have found previously (Ro & Clark, 2013). Trait measures had a hierarchical structure which, at the 5-factor level, reflected neuroticism/negative affectivity (N/NA), (low) sociability, disinhibition, (dis)agreeableness, and rigid goal engagement. When all measures were cofactored, a hierarchical structure again emerged which, at the 5-factor level, included (a) internalizing (N/NA and self-pathology vs. quality-of-life/satisfaction); (b) externalizing (social/interpersonal dysfunction, low sociability, and disagreeableness); (c) disinhibition; (d) poor basic functioning; and (e) rigid goal engagement. Results are discussed in terms of developing an integrated PD diagnostic model.