Temporal sequencing of change in trauma-related beliefs and therapeutic alliance during prolonged exposure and sertraline for chronic PTSD

Objective: Changes in trauma-related beliefs and therapeutic alliance have been found to temporally precede symptom reduction; however, it is likely these processes do not act in isolation but rather in interactive ways. Methods: The present study examined the temporal relationships between negative posttraumatic cognitions (PTCI) and therapeutic alliance (WAI) in 142 patients who were part of a randomized trial comparing prolonged exposure (PE) to sertraline for chronic PTSD. Results: Using time-lagged mixed regression models, improvements in the therapeutic alliance predicted subsequent improvements in trauma-related beliefs (d = 0.59), an effect accounted for by between-patient variability (d = 0.64) compared to within-patient variability (d = .04) giving weaker support to the causal role of alliance on outcome. Belief change did not predict improvements in alliance and neither model was moderated by treatment type. Conclusion: Findings suggest alliance may not be an independent driver of cognition change and point to the need for additional study of the impact of patient characteristics on treatment processes.