RESUMO
BACKGROUND: Childhood obesity is highly prevalent and carries substantial health consequences. Childhood obesity interventions have had mixed results, which may be partially explained by the absence of theory that incorporates broader family context and methods that address implementation challenges in low-resource settings. Communities for Healthy Living (CHL) is an obesity prevention program for Head Start preschools designed with careful focus on theory and implementation. This protocol paper outlines the design, content, implementation, and evaluation of CHL. METHODS/DESIGN: CHL integrates a parenting program co-led by Head Start staff and parents, enhanced nutrition support, and a media campaign. CHL content and implementation are informed by the Family Ecological Model, Psychological Empowerment Theory, and Organizational Empowerment Theory. The intervention is directed by community-based participatory research and implementation science principles, such as coleadership with parents and staff, and implementation in a real world context. CHL is evaluated in a three-year pragmatic cluster-randomized trial with a stepped wedge design. The primary outcome is change in child Body Mass Index z-score. Secondary outcomes include children's weight-related behaviors (i.e., diet, physical activity, screen use, and sleep), parenting practices targeted at these behaviors (e.g., food parenting), and parent empowerment. The evaluation capitalizes on routine health data collected by Head Start (e.g., child height and weight, diet) coupled with parent surveys completed by subsamples of families. DISCUSSION: CHL is an innovative childhood obesity prevention program grounded in theory and implementation science principles. If successful, CHL is positioned for sustained implementation and nationwide Head Start scale-up.