Abstract
OBJECTIVES: Centre-based childcare has been identified as a promising environment for obesity prevention in early childhood, but the longitudinal relationships between attending centre-based childcare and child obesity are not well understood. The objective of this systematic review is to evaluate the longitudinal associations between centre-based childcare attendance in early childhood and child body mass index compared with other childcare settings or parental care. Subgroup analyses will also be conducted to determine if socioeconomic factors and characteristics of the childcare setting modify the relationships. METHODS: Databases that will be searched include MEDLINE, Embase, Cumulative Index to Nursing and Allied Health Literature, the Cochrane Database and Web of Science. Longitudinal prospective cohort studies, retrospective cohort studies, case-control studies and intervention trials conducted in middle-income and high-income countries will be included in the search strategy. Sensitivity and subgroup analyses will be conducted to explore factors that may modify the findings. Study selection, data extraction, risk of bias and quality of evidence assessments will be conducted independently and in duplicate by two reviewers. Risk of bias will be assessed using the Risk Of Bias In Non-randomized Studies - of Exposure tool. Meta-analysis will be conducted using random effects models to account for between-study variation. Heterogeneity across included studies will be estimated using the I(2) statistic. If meta-analysis is not possible, a narrative summary will be provided. The quality of the evidence will be assessed using the Grading of Recommendations Assessment, Development and Evaluation tool. ETHICS AND DISSEMINATION: Ethical approval is not required for this study since no data will be collected. Findings aim to inform interventions and guide efforts in childcare settings to support optimal child growth. Results will be published in a peer-reviewed journal. Results may be of relevance for childcare and public health policy, researchers, parents and healthcare practitioners. PROSPERO REGISTRATION NUMBER: CRD42023436911.