Background: Few studies have examined the prevalence and treatment of narcissistic personality disorder (NPD).
Method: We systematically reviewed studies of NPD that used suitable diagnostic methods in adult nonclinical samples and evaluated their strengths and weaknesses. Searches were conducted of MEDLINE (using both MeSH category and free-word search terms), PsycINFO, and PsycLIT for articles in English from January 1980 to August 2008 using the terms Narcissis* and prevalence, of unpublished work identified via contacts with experts in the field, of books on personality disorders, and of reference lists from relevant articles and books. We evaluated articles using a 6-point epidemiologic quality tool that we developed. To determine the most efficacious treatments for NPD without other comorbidities, we performed searches using Narcissis*, pharmacology, clinical pharmacology, therapeutics, and psychotherapy for reports of controlled trials from January 1980 to August 2008.
Results: We identified 7 prevalence studies that had used a structured or semistructured interview, 5 of which scored 5/6 using the epidemiologic quality tool. Mean prevalence was 1.06%, and the range was 0% to 6.2%. We found no studies of treatment meeting our inclusion criteria.
Conclusions: There was an overall finding of a low prevalence of NPD in adult nonclinical samples. Changes in the classification system might promote further empirical investigations.
Published by Elsevier Inc.