Predictors of dropout from a randomized clinical trial of cognitive processing therapy for female veterans with military sexual trauma-related PTSD

Many veterans do not complete evidence-based treatments (EBTs) for posttraumatic stress disorder (PTSD). Veterans with military sexual trauma (MST)-related PTSD were shown to have higher than average rates of dropout from PTSD treatment in a national study of EBT implementation. Although predictors of dropout from EBTs have been identified, these factors are largely unmodifiable (e.g., age, service era). The purpose of the present study was to identify dynamic psychosocial predictors of dropout among female veterans from cognitive processing therapy (CPT). Data were utilized from 56 female veterans who participated in a randomized clinical trial investigating the effectiveness of CPT for MST-related PTSD. Dropout was defined continuously (i.e., number of sessions attended) and dichotomously (i.e., attending six or more sessions). Potential predictors included sociodemographic factors, psychotherapist fidelity, PTSD-related service connection, psychiatric symptom severity (i.e., PTSD, depression), trauma-related negative cognitions (about self, self-blame, world), and treatment expectations. Higher trauma-related negative cognitions about self-blame and lower trauma-related negative cognitions about self were protective against dropout. The current study generated testable hypotheses for further research on dynamic predictors of dropout from CPT in female veterans with MST-related PTSD. With replication, results may assist with identifying pre-treatment strategies to reduce dropout in this clinical population.