Reliability and Validity of the Structured Interview of Personality Organization (STIPO)

Background: Personality functioning has moved into the focus of psychiatric diagnosis since DSM-5 has introduced the Levels of Personality Functioning Scale for the assessments of personality disorders (PD). The 100-item Structured Interview of Personality Organization (STIPO) was developed for diagnosing personality functioning. The STIPO covers seven dimensions: (1) identity, (2) object relations, (3) primitive defenses, (4) coping/rigidity, (5) aggression, (6) moral values, and (7) reality testing and perceptual distortions. Methods: Validity and reliability of the 100-item instrument have been evaluated in 122 psychiatric patients. All patients were diagnosed according to the Diagnostic and Statistical Manual for Mental Disorders (DSM-IV) and were assessed by means of the STIPO. Moreover, all patients completed eight questionnaires that served as criteria for external validity of the STIPO. Results: Interrater reliability varied between intraclass correlations of .885 and 1.0, Crohnbach ́s α for the seven dimensions was .690 to .926. All a priori selected questionnaire scales correlated significantly with the corresponding STIPO dimensions. Patients with PD revealed significantly higher STIPO scores (i.e. worse personality functioning) than patients without PD; patients cluster B PD showed significantly higher STIPO scores than patients with cluster C PD. Conclusions: Interrater reliability, Crohnbach ́s α, concurrent validity, and differential validity of the STIPO are satisfying. The STIPO represents an appropriate instrument for the assessment of personality functioning in clinical and research settings.