Because few individuals endorsed most of the criteria for individual personality disorders, we collapsed the total criterion count into five categories to reduce the frequency of null cells. We have also tested the validity of this approach by examining the fit of the multiple-threshold model, which asks whether the number of endorsed criteria reflects differences of severity on a single normal continuum of liability. This assumption was supported for all 10 personality disorders (17–19). For ease of expression, we refer in this article to “personality disorders” in place of the more accurate but cumbersome term “five categories of endorsed criteria for personality disorders.” We previously reported the high inter-rater reliability for the assessed personality disorder obtained by two raters scoring 70 audiotaped interviews (27) (intraclass correlations for number of endorsed criteria ranged from 0.81 to 0.96).
