(PS9-96) The Relation Between Exposure Approach and Treatment Outcomes: A Moderation Analysis

Abstract Text: Exposure therapy is a highly efficacious treatment for anxiety, obsessive-compulsive disorder (OCD), post-traumatic stress disorder (PTSD), and other related disorders. Traditionally, emotional processing theory (EPT) has been used to describe the mechanisms (i.e., habituation) underlying exposure therapy. However, many researchers now argue that exposure therapy would be more effective if it were conducted in line with learning research (i.e., the inhibitory learning approach). A few studies have empirically tested whether the inhibitory learning approach led to better treatment outcomes than EPT, but the findings were mixed. Additionally, these studies have primarily focused on adults, and there is a dearth of research examining whether one approach is superior for children. Thus, the current study examines whether treatment outcomes between those who received EPT versus inhibitory learning approach exposures is moderated by age group (i.e., adult or child). Participants were 1,968 individuals who engaged in an intensive outpatient program for OCD, anxiety, PTSD, and related disorders between 4/2018 and 9/2023. In September 2019, the program switched from conducting exposures in line with EPT to the inhibitory learning approach. Of the full sample, 171 (8.7%) received EPT exposures while 1,797 (91.3%) received inhibitory learning exposures. The majority of the sample identified as female (61.1%), were adults (67.0%) and had a primary diagnosis of OCD (70.5%). Participants took self-report measures that corresponded with their primary diagnosis at pre- and post-treatment which were used to calculate percent symptom reduction. A moderation analysis was conducted using R with exposure approach (EPT or inhibitory learning) predicting percent symptom reduction, moderated by age group (i.e., adult or child). The results indicate that age group did not moderate the relationship between exposure type and symptom reduction (p = .128). However, there was a main effect of exposure approach, such that the inhibitory learning approach predicted greater symptom reduction (ß = 0.136, p = .003). In other words, an individual who received inhibitory learning approach exposures is predicted to have 13.6% greater symptom reduction than someone who received EPT exposures, regardless of age group. The findings of the current study add to the burgeoning literature suggesting that the inhibitory learning approach may result in better treatment outcomes than exposures done in accordance with EPT and this result was evident for both adults and children. Important clinical implications of this research indicate that exposure therapy for children should focus on inhibitory learning principles rather than on habituation to promote positive outcomes. Our findings align with a study conducted by Kennedy & Hawkes (2021) which found that inhibitory learning approach exposures were feasible and acceptable for children and led to better outcomes than EPT exposures.