An investigation of differential item functioning across gender of BPD criteria

Gender differences in prevalence rates of Borderline Personality Disorder (BPD) may reflect true differences between groups or may reflect some form of gender bias in diagnostic criteria. The detection of differential item functioning (DIF) using item response theory methods provides a powerful method of evaluating whether gender differences in prevalence rates of BPD reflect true mean differences or criterion bias. The aim of the current study was to evaluate gender-based DIF in DSM BPD criteria. The Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV) Axis II Personality Disorders (SCID-II: First, Spitzer, Gibbon, Williams, & Benjamin, 1994) was administered to 747 adult inpatients. Results indicated DIF for 2 BPD criteria (impulsivity and uncontrolled anger), such that it was easier for these items to be endorsed for men compared with women at the same level of latent trait. At the level of the test, men were expected to be rated slightly higher than women on the SCID-II at the same level of latent BPD liability. Implications of these results for research and clinical assessment are discussed.