4 - (SYM 103) The Impact of Modifications and Adaptations on Intervention Outcomes: An Examination of the Implementation of the Peer Body Project on College Campuses

College campus mental health services struggle to meet students' growing needs. Eating disorders (EDs) are of particular concern, as treatments are intensive, expensive, and vary depending on diagnosis, making them difficult to implement and sustain. One solution is for peer educators (PEs) to deliver cost-effective group-based prevention programs such as the Peer Body Project (PBP) (Stice et al., 2013), which reduces thin-ideal internalization, body dissatisfaction, and ED symptoms. While PBP shows promise, moving to large-scale implementation is often a challenge for evidence-based interventions (EBIs) due to differences in setting, participants, and providers' post-developer oversight. Modifications to EBIs may allow for better fit in the contexts where they are being implemented, permitting long-term sustainability. Alternatively, if modifications reduce fidelity to EBIs as developed and tested, they may be less effective.

The study used recordings from a larger randomized implementation-effectiveness trial of PBP on 63 college campuses (Stice et al., 2023) to identify both general and cultural modifications and test their impact on treatment outcomes. The sample included 173 session recordings across 93 groups from 34 colleges. Participating PEs (n = 177) were mostly female (95%) and White (77%), with a mean age of 21.3. Group participants (n = 486) were mostly female (98%) and White (50%), with a mean age of 21. Exploratory analyses assessed if PE characteristics, group ethnic/racial composition, and ethnic/racial matching of participants and PEs predicted modifications to PBP.

Modifications occurred in every PBP group, with 50% of groups implementing cultural modifications, and did not predict treatment outcomes. Ethnicity/race did not moderate this relationship. The more groups a PE facilitated, the more general and cultural modifications they implemented. Greater ethnic/racial diversity in group composition and ethnic/racial matching between an individual participant and other group participants predicted more cultural modifications. Cultural modifications predicted better outcomes on thin-ideal internalization when there is an ethnic/racial match between an individual and their PE.

The study suggests that modifications do not detract from PBP effectiveness and may improve population fit without diluting core intervention ingredients. Implications for sustainability and future directions will be discussed.