Comorbidity of DSM-IV personality disorders in a nonclinical sample

The issue of comorbidity within the Axis II personality disorders was explored using a large sample of university students who were administered the Coolidge Axis II Inventory (CATI). Comorbidity patterns with this normal sample were compared with recent clinical data reported by several other researchers. The results confirm the high degree of comorbidity within Axis II and the similarity in the comorbidity patterns with clinical and nonclinical samples. With the CATI, a 30.4% comorbidity rate was obtained for Histrionic and Narcissistic Personality disorders (Pd). The paranoid, passive-aggressive and borderline personality disorder traits were comorbid with several other Pds. For Cluster A, there was low comorbidity except for Paranoid Pd and Schizotypal Pd. With Cluster B, the co-occurrence was moderate to strong. A moderate amount of interrelationship was obtained for the Cluster C Pds. The DSM-IV clusters were also strongly interrelated. An additional finding was the similarity between self-report and structured interview methodology in obtained personality disorder comorbidity.