Optimization of a Multicomponent Intervention to Foster Functional Recovery After Breast Cancer Treatment

Breast cancer treatment creates physical, emotional, and practical challenges that disrupt routines and activities. After completion of curative treatment, one-third of cancer survivors report participation restrictions, defined as difficulties performing valued activities that reflect life roles. Participation restrictions can persist two to six years after breast cancer treatment, imposing personal and societal costs by hindering one's ability to fulfill career, civic, and caregiving roles. Addressing participation restrictions reflects the Cancer Moonshot Initiative call for research on ways to reduce the debilitating effects of cancer, yet there are no evidence-based interventions that are ready for large scale implementation.

Most survivorship research has targeted symptom management, yet that does not always translate into greater participation in role-relevant activities. Recent evidence demonstrates that participation can be enhanced even in the absence of symptom reduction. There are now a number of interventions that aim to increase participation through various combinations of self-management strategies like goal setting and problem-solving, priority elicitation, and education about activity adaptation, environmental modification, and energy management. While studies indicate that these strategies are feasible and appear to enhance participation, each study uses a different blend of strategies that are often not well-specified, leaving us uncertain as to which strategies of the multi-component interventions are most potent and which may be unnecessary. This uncertainty reduces reproducibility and limits large-scale implementation.

Our overall goal is to identify mechanisms of action by which we can reliably enhance participation in role-relevant activities after breast cancer treatment. The Multiphase Optimization STrategy (MOST) framework of intervention development uses engineering principles to build multi-component interventions that are both potent (i.e., produce clinically relevant outcomes) and parsimonious (i.e., contain no inactive ingredients). The first phase of MOST creates a conceptual model linking intervention components (i.e., strategies) and their intended targets and identifies an optimization criterion by which success will be judged. Our optimization criterion is to find the combination of intervention components that has the largest effect on participation restrictions. This proposal reflects the second phase of MOST, the optimization phase, where we will evaluate the degree to which each intervention component exerts an independent or synergistic effect on participation restrictions. The optimization phase ensures that the resulting intervention is composed only of components that are contributing to the outcome of interest.

We will use a factorial experiment in our optimization trial to test three intervention components that we and others have used with breast cancer survivors: (1) priority-elicitation and session tailoring; (2) cancer survivorship education; and (3) guided application involving goal setting, problem-solving, and action planning. The components each have a modest evidence base supporting their efficacy to reduce participation restrictions. However, they have different profiles regarding a) the time survivors need to invest and b) the skills practitioners need to successfully deliver. To move the science forward, it is crucial to develop a potent yet parsimonious intervention with empirically-supported mechanisms of action.

Our research question is: Which components alone or in combination have the greatest impact on participation restrictions? Using the MOST framework, we will conduct an optimization trial with a factorial design. We will recruit 352 breast cancer survivors reporting participation restrictions in the first year following curative treatment and randomize them to receive combinations of the 3 components.