Improving nutrition and physical activity environments of family child care homes: the rationale, design and study protocol of the ‘Healthy Start/Comienzos Sanos’ cluster randomized trial

BACKGROUND: Early childhood is a crucial time to foster healthy eating and physical activity (PA) habits, which are critical for optimal child health, growth and development. Child care facilities are important settings to promote healthy eating and PA and prevent childhood obesity; however, almost all prior intervention studies have focused on child care centers and not family child care homes (FCCH), which care for over 1.6 million U.S. children. METHODS: This paper describes Healthy Start/Comienzos Sanos, a cluster-randomized trial evaluating the efficacy of a multicomponent intervention to improve nutrition and PA environments in English and Spanish-speaking FCCH. Eligible child care providers complete baseline surveys and receive a two-day FCCH observation of the home environment and provider practices. Parent-consented 2–5 year-old children are measured (height, weight, waist circumference), wear accelerometers and have their dietary intake observed during child care using validated protocols. FCCH providers are then randomly assigned to receive an 8-month intervention including written materials tailored to the FCCH providers’ need and interest, videos, peer support coaching using brief motivational interviewing, and periodic group meetings focused on either nutrition and PA (Intervention) or reading readiness (Comparison). Intervention materials focus on evidence-based nutrition and physical activity best practices. The initial measures (surveys, two-day observation of the FCCH and provider practices, child diet observation, physical measures, and accelerometer) are assessed again 8 and 12 months after the intervention starts. Primary outcomes are children’s diet quality (Healthy Eating Index), time in moderate and vigorous PA and sedentary PA during child care. Secondary outcomes include FCCH provider practices and foods served, and PA environments and practices. Possible mediators (provider attitudes, self-efficacy, barriers and facilitators) are also being explored. Process evaluation measures to assess reach, fidelity and dose, and their relationship with dietary and PA outcomes are included. DISCUSSION: Healthy Start/Comienzos Sanos fills an important gap in the field of childhood obesity prevention by rigorously evaluating an innovative multicomponent intervention to improve the nutrition and physical activity environments of FCCH. TRIAL REGISTRATION: (# NCT02452645) ClinicalTrials.gov Trial registered on May 22, 2015. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s12889-019-6704-6) contains supplementary material, which is available to authorized users.