(PS12-B44) Gender Differences in Psychological Outcomes Following Surf versus Hike Therapy Among U.S. Service Members

Surf and Hike Therapies have demonstrated effectiveness as adjunct interventions for service members (SM) with major depressive disorder (MDD). However, less is known about who benefits most from these interventions. This study explores whether intervention outcomes following a randomized controlled trial of Surf and Hike Therapy for SM with MDD differ by gender (N = 96; women, n = 50; men, n = 46). Clinician-administered and self-report measures (depression, anxiety, positive affect, negative affect, resilience, pain) were completed at preprogram, postprogram, and 3-month follow-up, and brief measures (depression/anxiety, positive affect) were completed before and after each session. Multilevel modeling results showed significant improvements for women and men across all outcomes, expect pain, from preprogram to follow-up, and results did not differ by gender. However, within sessions, women reported greater improvements in depression/anxiety (B = -0.93, p = 0.05) and positive affect (B = 3.73, p = .001). Only one three-way interaction was significant (B = 2.81, p = .016), demonstrating that change in positive affect scores within sessions was greater for female participants in Hike Therapy. Overall, results demonstrate that both genders benefit from Surf and Hike Therapies, but women exhibit a better response in immediate psychological outcomes compared to men. Implications for care provision will be discussed.