Refining personality disorder diagnosis: Integrating science and practice

Objective: Personality disorder researchers are currently evaluating a range of potential solutions to problems with the DSM-IV diagnostic categories. This article proposes changes to the diagnostic categories and criteria based on empirical findings from a national sample of patients with personality disorder diagnoses. Method: The Shedler-Westen Assessment Procedure (SWAP-200) is a personality assessment tool designed to capture the richness and complexity of clinical personality descriptions while providing reliable and quantifiable data. A national sample of experienced psychiatrists and psychologists used the SWAP-200 to describe either their conceptions (prototypes) of personality disorders (N=267) or current patients with personality disorder diagnoses (N=530). Results: Clinicians' conceptions of personality disorders and their descriptions of actual patients overlapped with the DSM descriptions but also differed in systematic ways. Their descriptions were clinically richer than the DSM descriptions and placed greater emphasis on patients' mental life or inner experience. The study identifies potential diagnostic criteria that may be more defining of personality syndromes than some of the current DSM criteria. Conclusions: Diagnostic criterion sets should be expanded to better address the multiple domains of functioning inherent in the concept of personality and should more explicitly address patients' mental life or inner experience. The authors offer recommendations for revision of the diagnostic categories and criteria and also propose a prototype matching approach to personality disorder diagnosis that may overcome limitations inherent in the current diagnostic system.