Finally, a number of study limitations need to be highlighted. Foremost among these relates to the exploratory nature of this study. As such, the findings of this study need to be replicated in other national surveys. Second, diagnoses of disorders were based on structured interviews by lay interviewers and, while informed by DSM-IV criteria, are not clinical assessments and are based on retrospective self-reports. Admittedly, the NESARC has demonstrated fair to good reliability for all 10 DSM-IV PDs in the general population, provided extensive information including their prevalence, correlates, and comorbidity, and their important role in the incidence and persistence of other disorders (Eaton et al., 2012; Hasin et al., 2011; Skodol et al., 2011). Third, the one-time assessment of PD limits this study to cross-sectional analysis and does not allow assessment of directionality between PD and other lifetime Axis I disorders. Fourth, the PDs were assessed at different time periods and may have introduced some bias in the associations with Axis I disorders at Wave 2, although Eaton and colleagues (2011) compared Wave 2 borderline PD with Wave 1
