5 - (IOP 38) Does Adapting a Treatment to Context Impact Sustainment? Testing Sustainment Predictors, Mechanisms, and Outcomes from a Hybrid Type 2 Cluster-randomized Trial in Community Mental Health

Background: Research on the implementation of evidence-based treatments (EBTs) has advanced rapidly. However, research on the sustainment of implemented EBTs remains limited. Indeed, the lack of research on sustainment has been called “one of the most significant translational research problems of our time” (Proctor et al., 2015, p. 2). Advancing research on EBT sustainment – and congruent with ABCT’s mission of furthering cognitive behavioral research - the present study tested the sustainment of two versions of a transdiagnostic, cognitive behavioral treatment (the Transdiagnostic Intervention for Sleep and Circadian Dysfunction [TranS-C]) for patients with serious mental illness. Specifically, in a hybrid type 2 cluster-randomized controlled trial, 10 CMHCs were randomized to receive Standard TranS-C or a version of TranS-C that had been adapted to “fit” the CMHC context (i.e., Adapted TranS-C), aligning with the 2025 ABCT convention theme.

Adapted and Standard TranS-C were implemented in CMHCs via facilitation and train-the-trainer, after which implementation support was gradually withdrawn. The aims of the present study were to evaluate: (1) Does adapting TranS-C to fit the CMHC context predict improved sustainment outcomes, with respect to continued activities, benefits, and capacity (per the framework of Shediac-Rizkallah & Bone, 1998), and (2) Are these improvements mediated by providers’ perceptions of improved “fit,” with respect to appropriateness, acceptability, and feasibility?

Method: We collected surveys on sustainment outcomes (activities, benefits, capacity) and fit (appropriateness, acceptability, feasibility) from participating CMHC providers (N = 134) beginning three months after implementation support in CMHCs had been withdrawn (Mean time post-implementation = 8 months). Multilevel modeling was used for Aim 1. Structural equation modeling was used for Aim 2.

Results: For Aim 1, TranS-C condition (Adapted vs. Standard) did not predict sustainment outcomes (p values > 0.05). However, in post-hoc analyses, there were significant interactions between treatment condition and amount of time that had passed since implementation support had been withdrawn. Specifically, more time since implementation was associated with lower sustained activities, benefits, and capacity for providers in the Adapted condition, relative to the Standard condition (p values < 0.05). In Aim 2, TranS-C condition indirectly predicted sustainment outcomes through perceived feasibility (i.e., confidence intervals of indirect effects did not cross zero). Specifically, relative to Standard TranS-C, Adapted TranS-C predicted less feasibility, which in turn was associated with lower sustained benefits and capacity.

Conclusion: To our knowledge, this is the first study to test whether systematically adapting a treatment to context predicts sustainment outcomes. Surprisingly, results from these analyses suggest that the changes made to TranS-C to fit the CMHC context (e.g., shortening the treatment training and modules to fit busy CMHC schedules) may have reduced sustainability. Interpretations will be explored, and implications for future research on the implementation and sustainment of EBTs will be discussed.