Mechanisms of change in treatments of posttraumatic stress disorder: Investigating the mediating effects of negative mood state and therapeutic alliance
This study evaluated negative mood state and therapeutic alliance as two potential mechanisms of therapeutic change in Posttraumatic Stress Disorder (PTSD) symptom severity and affect regulation. The analyses used data collected as part of Ford and colleagues' (2011) randomized control trial (RCT) comparing the efficacy of Trauma Affect Regulation: Guide for Education and Therapy (TARGET) an affect-based intervention for PTSD, to Present-Centered Therapy (PCT), among women with PTSD. Ford et al. (2011) found significant treatment effects (changes in PTSD symptom severity and affect regulation) for both treatment groups. This study addressed gaps in the current literature by using a moderated mediational design to investigate why these effects were found and whether magnitude of the effect varied by treatment. The findings provide limited support for the study hypotheses. Namely, results of hierarchical linear modeling indicated that negative mood state did have a significant indirect effect on affect regulation in both the overall sample and in the TARGET group, but not in the PCT group. Negative mood state also had a significant indirect effect on PTSD symptoms in the TARGET group, but not the PCT group or overall sample, suggesting a conditional indirect effect of TARGET on PTSD symptoms. Results indicated that therapeutic alliance did not have a significant indirect effect on either PTSD symptoms or affect regulation in the overall sample or in either treatment group. The results specific to negative mood state are a valuable contribution to the extant literature on treatments for PTSD. First, the findings support the theoretical justification of TARGET and further understanding of affect regulation as a mechanism of change in PTSD treatment. Second, the results provide support for addressing affect regulation directly in PTSD treatment. Third, the results provide support for the use of negative mood state as potential indicator of change in affect regulation during treatment, and as such an important factor to address in treatment. The results suggest a complicated causal process in PTSD symptom change, and lay the groundwork for future research that can enrich both the theory and practice of PTSD treatment.
Stimmel, Matthew, "Mechanisms of change in treatments of posttraumatic stress disorder: Investigating the mediating effects of negative mood state and therapeutic alliance" (2013). ETD Collection for Fordham University. AAI3600979.