A generic logic model for physical activity interventions for the cardiac population using intervention mapping

Introduction Regular physical activity is important in the secondary prevention of cardiovascular disease. But many cardiac patients have difficulty establishing lifelong physical activity habits, even after completion of an exercise-based cardiac rehabilitation programme. There is a need for effective interventions to support cardiac patients' physical activity. Such interventions are often complex behaviour change interventions whose design should be grounded in programme theory, i.e., a description of how the intervention is expected to lead to its effects and under what conditions. A logic model is often used to communicate programme theory [1]. Purpose The purpose of this work was to describe a generic logic model for behaviour change interventions to increase and maintain physical activity among patients who have had an acute cardiac event. Methods We applied the Intervention Mapping approach [2] to develop a generic logic model that is both data- and theory-driven, i.e. informed by research evidence and behaviour change theory. The at-risk behaviour for the individual cardiac patient was defined as "insufficient independent long-term maintenance of heart-healthy physical activity", compounded by the environmental factor "lack of support provision for long-term independent physical activity" from the healthcare providers and people in the patient’s interpersonal environment. We defined performance objectives by asking the questions: "What do people who had an acute cardiac event need to do to increase and maintain their heart-healthy physical activity?" and "What do the healthcare providers and people in the patient’s interpersonal environment need to do to encourage and support the patient in being physically active?" The performance objectives specify what actions are required of the individuals targeted in the intervention. We selected determinants corresponding to performance objectives based on empirical evidence from systematic reviews and based on behaviour change theory such as the Reasoned Action Approach (RAA) and the Health Action Process Approach (HAPA). Results Central elements of the logic model are presented in table 1. The logic model includes 18 performance objectives and 13 determinants, supported by empirical evidence from 40 scientific publications. Conclusion The generic logic model serves as a collection of current knowledge regarding increasing and maintaining physical activity among the cardiac population and can be used for a number of purposes: as a foundation for developing new interventions; as a blueprint against which to compare and/or solidify the programme theory of existing interventions; as a conceptual framework for designing evaluations of interventions; as a current evidence map from which to identify research gaps; and as a point of reference for reflecting on one’s own health behaviour.Table 1.Elements of the logic model.