Examining sex differences in DSM-IV borderline personality disorder symptom expression using Item Response Theory (IRT).

Limited literature suggests that there may be differences in how women and men experience borderline personality disorder (BPD) symptoms. The aim of the current study was to use methods based on item response theory (IRT) to examine whether, when equating for levels of BPD symptom severity, there are sex differences in the likelihood of reporting DSM-IV BPD symptoms. We conducted these analyses using a large, nationally representative sample from the USA (n = 34,653), the second wave of the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC). Data from women and men were compared. There were statistically and clinically significant sex differences for 3 out of the 9 DSM-IV BPD symptoms. We found that women were more likely to experience suicidal/self-mutilation behavior, affective instability and chronic feelings of emptiness and tended to be less likely to endorse impulsivity at lower levels of borderline personality disorder severity than men, while affective instability and chronic feelings of emptiness appeared to be significantly less discriminant in terms of severity in men than in women. There were no significant differences between women and men on the remaining DSM-IV symptoms. Overall, our findings indicate substantial sex differences in borderline personality disorder symptom expression. Although our results may reflect sex-bias in diagnostic criteria, they are in keeping with recent arguments suggesting that BPD could be understood as a clinical phenomenon that may partially differ in men and women.