STEP-UP Brazil: Development and evaluation of a self-management program based on education and exercise for plantar heel pain

Plantar heel pain (PHP), often referred to as plantar fasciitis, is one of the most common musculoskeletal conditions affecting the foot and has a substantial impact on pain, mobility, participation in occupational and recreational activities, and quality of life. Although international clinical guidelines recommend education, load management, stretching, and therapeutic exercise for its treatment, much of the available evidence derives from interventions delivered in controlled settings under professional supervision. Within the Brazilian Unified Health System (SUS), models that promote autonomy, active participation, and reduced reliance on face-to-face care may improve access to and sustainability of care. However, structured self-management programs for PHP developed for the Brazilian context and comprehensively evaluated in terms of clinical effectiveness, mechanisms of response, heterogeneity of treatment effects, and economic value are still lacking. The Self-management Therapy, Education and Progressive exercise for plantar heel pain (STEP-UP Brazil) project aims to develop and evaluate a self-management program based on health education, load management, and progressive therapeutic exercise for individuals with PHP. Specifically, the project will develop and refine the intervention based on the best available evidence and an explicit intervention theory; evaluate its clinical effectiveness, adherence, satisfaction, and safety compared with usual care; investigate physical-functional, psychosocial, and behavioral mechanisms that mediate its effects and individual characteristics that moderate treatment response; and determine its cost-effectiveness and cost-utility, generating evidence to support future implementation and scalability within the SUS. STEP-UP Brazil will be conducted as a research program guided by the Medical Research Council framework for developing and evaluating complex interventions and will comprise four interrelated stages. In Stage 1, the intervention will be developed through evidence synthesis, construction of an intervention theory and component matrix, development of intervention materials, evaluation by an expert panel using a modified Delphi process, and assessment of comprehensibility and usability by the target population. In Stage 2, a randomized, controlled, superiority clinical trial with two parallel arms, 1:1 allocation, and blinded outcome assessment will be conducted in 90 adults with PHP. The intervention group will receive STEP-UP Brazil for 12 weeks, while the control group will receive usual care. The primary outcome will be pain intensity during the first steps after rest. Additional outcomes will include foot pain and function, physical-functional capacity, psychosocial and behavioral factors, physical activity, quality of life, adherence, satisfaction, and safety, assessed at baseline (T0), after the 12-week intervention (T12), and at the 24-week follow-up (T24). In Stage 3, mediation analyses will investigate whether physical-functional and cognitive-behavioral changes at T12 explain clinical effects at T24, while moderation analyses will assess which baseline characteristics modify the response to the intervention. In Stage 4, a prospective economic evaluation will be conducted from the SUS and societal perspectives, including cost-effectiveness and cost-utility analyses, with estimation of incremental costs, clinical effects, quality-adjusted life years (QALYs), incremental cost-effectiveness ratios, and associated uncertainty. We expect to develop an evidence-based, theoretically grounded, standardized, reproducible self-management intervention for PHP that is appropriate for the Brazilian population and to determine whether STEP-UP Brazil provides greater clinical benefits than usual care. Beyond establishing whether the intervention works, the project is expected to advance understanding of how it works and for whom it works best, identifying mechanisms and characteristics associated with heterogeneity in treatment response. We also expect to determine whether its additional benefits justify the resources required for its delivery, thereby generating evidence regarding its economic value. By integrating systematic intervention development, clinical effectiveness, mechanisms of response, individual heterogeneity, and economic evaluation, STEP-UP Brazil may advance knowledge on self-management interventions in musculoskeletal rehabilitation and establish the scientific basis for future implementation and scalability within the SUS. Additionally, the project will contribute to training human resources in clinical research, rehabilitation, mechanism analysis, and economic evaluation, and to disseminating its findings through scientific outputs and publications with national and international reach.