Establishing Levels of Personality Functioning Using the Structured Interview of Personality Organization (STIPO-R):...

Both the new ICD-11 and the latest Alternative DSM-5 Model for Personality Disorders focus on self and interpersonal functioning as the central feature of personality pathology, also acknowledging that personality disorders are organized along a dimensional continuum of severity. This revised understanding is in line with long-standing psychodynamic conceptualisations of personality pathology, in particular Kernberg's object relations model of personality organization. Despite existing evidence for the clinical utility of the derived Structured Interview of Personality Organization (STIPO-R), empirical support for the identification of clear cut-points between the different levels of personality functioning is missing. For this purpose, a total of 764 adult participants were recruited across two clinical (outpatient and inpatient) settings (n = 250) and two non-clinical (university students and general community) samples (n = 514). Results from the mixture modeling suggested the existence of five groups across the clinical and non-clinical samples that covered: healthy personality functioning, maladaptive personality rigidity, and mild, moderate, and severe levels of personality pathology. All five indicators of personality organization were found to be reliable predictors of personality pathology. Of the five STIPO-R indicators, Aggression and Moral Values had the most discriminative power for differentiating between the Mild, Moderate, and Severe personality disorder groups. Implications of these findings are discussed.