Sex differences in DSM-IV posttraumatic stress disorder symptoms expression using item response theory: A population-based study

Abstract

Background: Whether there are systematic sex differences in posttraumatic stress disorder (PTSD) symptom expression remains debated. Using methods based on item response theory (IRT), we aimed at examining differences in the likelihood of reporting DSM-IV symptoms of PTSD between women and men, while stratifying for major trauma type and equating for PTSD severity.

Method: We compared data from women and men in a large nationally representative adult sample, the National Epidemiologic Survey on Alcohol and Related Conditions. Analyses were conducted in the full population sample of individuals who met the DSM-IV criterion A (n=23,860) and in subsamples according to trauma types.

Results: The clinical presentation of the 17 DSM-IV PTSD symptoms in the general population did not substantially differ in women and men in the full population and by trauma type after equating for levels of PTSD severity. The only exception was the symptom "foreshortened future", which was more likely endorsed by men at equivalent levels of PTSD severity.

Limitations: The retrospective nature of the assessment of PTSD symptoms could have led to recall bias. Our sample size was too small to draw conclusions among individuals who experienced war-related traumas.

Conclusions: Our findings suggest that the clinical presentation of PTSD does not differ substantially between women and men. We also provide additional psychometric support to the exclusion of the symptom "foreshortened future" from the diagnostic criteria for PTSD in the DSM-5.

Keywords: Criteria; Differential item functioning (DIF); Item response theory (IRT); National study; Posttraumatic stress disorder; Sex differences; Symptoms.