Living with the enemy: A causal inference analysis of military sexual trauma and posttraumatic stress disorder symptomology

Background: Military sexual trauma (MST) has been linked to a range of negative mental health outcomes-posttraumatic stress disorder (PTSD) most notably. This article uses a causal inference framework based on the Rubin Causal Model to investigate the relationship between MST exposure and PTSD symptom severity. Methods: Using data from 2488 treatment-seeking veterans and service members, we reconstructed a hypothetical randomized control trial consisting of a group with MST exposure and one without. We used Student's test-statistic and estimated regression coefficients to study the isolated effect of MST history on PTSD symptomology. Results: Results of our Student's test statistics revealed that the MST and no-MST groups had different mean PCL-5 total scores (t = -3.54, Fisher's p < .001). Estimated regression coefficients showed that a history of MST was associated with higher PCL-5 total scores (beta= 3.37, Fisher's p < .001), as well as with higher intrusion (beta = 4.43, Fisher's p < .001), negative cognitions and mood (beta = 2.28, Fisher's p = .013), and hypervigilance (beta = 3.57, Fisher's p < .001) cluster scores. There was no significant difference in levels of avoidance between the two groups. Limitations: Results must be interpreted with caution as the model is unable to control for all known confounding variables. Conclusion: Treatment-seeking veterans and servicemembers with a history of MST demonstrated higher global PTSD severity. More research is necessary to examine how unique characteristics and circumstances of MST exposure may affect PTSD presentations and symptoms.