Rethinking randomized controlled trials: Using the multiphase optimization strategy framework to optimize...

Multicomponent biobehavioral and psychosocial interventions in rehabilitation psychology have traditionally employed a "treatment package" approach, which bundles multiple components into a single intervention. While this method can be practical, it often fails to provide detailed insights into the effectiveness of each component within the package. This lack of granularity can obscure which elements are most beneficial and which may be superfluous or even detrimental. In contrast, the multiphase optimization strategy (MOST) presents a novel framework inspired by engineering principles. MOST is designed to optimize and refine multicomponent interventions by systematically evaluating each component's contribution to the overall intervention while simultaneously considering real-world constraints. This method allows a more precise understanding of how each component impacts the intervention's efficacy, efficiency, and scalability. Using MOST, researchers can iteratively test, refine, and optimize intervention components before conducting comprehensive randomized controlled trials. This commentary highlights the limitations inherent in traditional randomized controlled trial approaches, which may overlook the nuances of individual intervention components. It advocates for using the MOST framework for developing and testing multicomponent interventions in rehabilitation psychology. By adopting MOST, researchers can enhance the precision and impact of their interventions, leading to more efficient research and increased translation to clinical practice. (PsycInfo Database Record (c) 2026 APA, all rights reserved).