Predicting treatment response in psychotherapy for posttraumatic stress disorder: A pilot study

Prediction of treatment response to trauma-focused psychotherapy remains a difficult task. This study evaluated treatment response to Brief Eclectic Psychotherapy for posttraumatic stress disorder (BEPP) dependent on pre-treatment variables, symptom progression, and manual adherence. We tested differences in pre-treatment variables and symptom time course between treatment responders and non-responders in 27 patients, using exact regression analyses and general linear models. Associations of therapists´ adherence to the treatment manual during different therapy phases with response status were also studied using independent samples t-test. Lower education and complete inability to work were negatively related to therapy outcome. Significant differences in symptom time course between responders and non-responders were detected from session nine onwards, whereas adherence to treatment was not related to outcome during any treatment phase. Our results indicate that early identification of treatment response may meaningfully expand previous research on outcome predicton based on pre-treatment variables in trauma-focused psychotherapy. Furthermore, adaptations of treatment protocols for specific groups of patients with increased risk of poor treatment outcomes may be advisable. If replicated by more naturalistic designs, our results could contribute towards limiting the requirement of strict manual adherence to efficacy studies in posttraumatic stress disorder treatment research.