With traditional cutoff scores, too few individuals met full DSM-IV criteria for the 10 personality disorders for statistical analysis (17–19). We therefore modeled the personality disorders as an ordinal count of the number of positively endorsed criteria. Furthermore, defining a criterion to be present with a score of 1 or higher produced more stable results than using a cutoff of 2 or higher. This approach is justified by results from previous studies of these 10 personality disorders (17–19) in which, using a multiple-threshold model, we showed that the four response options for scoring individual personality disorder criteria reflected varying levels of “severity” on a single continuum of liability.
