Date of Award

Fall 12-2009

Degree Type


Degree Name

Doctor of Philosophy (PhD)



First Advisor

Erin B. McClure-Tone

Second Advisor

Page Anderson

Third Advisor

Bekh Bradley-Davino

Fourth Advisor

Christopher C. Henrich


Elucidating factors associated with adherence to treatment for physical and mental health conditions is important, given well-documented associations between non-adherence and poor treatment outcomes. Researchers have worked to identify such factors; however, most studies focus on adherence to medical, rather than, psychological treatments. Clarifying variables that predict adherence to psychotherapy is particularly important for individuals with post-traumatic stress disorder (PTSD), for whom treatment, which typically involves exposure to trauma-related stimuli and imagery, can be aversive. It may consequently be associated with high nonadherence rates, even though studies indicate that greater adherence to PTSD treatment relates to better treatment outcomes. Research needs to identify factors that increase or decrease the likelihood that affected individuals will enter and complete therapy. Although several studies to date have examined adherence to treatment for PTSD, this literature is limited on several fronts. First, studies on psychotherapy adherence have identified few consistent predictors of treatment adherence. Second, adherence to psychotherapy is rarely a central focus of treatment-related research; more typically, researchers treat adherence as secondary in importance to treatment outcomes. Third, little research on psychotherapy adherence has been theoretically driven. Fourth, little adherence research has focused on combat veterans with PTSD, who tend to have particularly poor treatment outcomes. Especially lacking is knowledge about predictors of adherence in veterans who have recently returned from combat; most research focuses on veterans of the Vietnam War, many of whom were initially traumatized decades earlier. The study tested the hypothesis that elevated reports of a specific type of PTSD symptom--avoidance/emotional numbing-- predicted poorer adherence to treatment in 160 veterans who received psychotherapy. No significant associations between avoidance and emotional numbing symptoms and adherence were found. However, emotional numbing was negatively related to psychotherapy adherence. Other variables typically related to PTSD and treatment outcomes were found to be important predictors of psychotherapy adherence and completion/noncompletion of therapy.

Included in

Psychology Commons