Implementation strategies used in policy, systems, and environmental interventions addressing obesity-related outcomes in early childhood education settings: a systematic review

Background: Policy, systems, and environmental (PSE) approaches, including those enacted in early childhood education (ECE) settings, can improve child health outcomes. The use of implementation strategies, or the ways in which these approaches are enacted across settings, may modify intervention impact. Therefore, the purpose of this review was to examine the implementation strategies used among interventions utilizing PSE approaches in the ECE setting. Methods: Seven databases including MEDLINE, PubMed, Web of Science, and EMBASE, were searched for interventions in ECE settings including children (0–6 years) that utilized ≥ 1 PSE approach. Eligible studies included either a child-level outcome (i.e., weight, physical activity, or diet) or an environmental outcome (i.e., nutrition and physical activity environment). Data extracted included study characteristics, description of the intervention, and description of the implementation of the intervention. Implementation strategies were coded using the School Implementation Strategies Translating ERIC Resources (SISTER) taxonomy. The Downs and Black checklist was completed to assess study quality. Results: One hundred and four studies representing 97 interventions were identified. Fourteen (14%) did not report any implementation strategies. Of the remaining 83 interventions reporting implementation strategies, the mean number of implementation strategies employed per intervention was 3.8 (± 2.3) (range 1–11). However, few interventions (5/83, 6%) clearly named and defined implementation strategies. Most implementation strategies came from the “train and educate stakeholders” SISTER domain (177/318, 56%), and the most frequently used implementation strategy was “conduct educational meetings (50/83, 60%). Most studies were classified as good (59/104, 57%) or fair (40/104, 38%) quality. Conclusions: In this review, many interventions appeared to use multiple implementation strategies to support ECE PSE interventions, though few explicitly documented or described those strategies. These findings suggest that more precise documentation of implementation strategies is needed to enhance replication and scalability of ECE interventions. Registration: PROSPERO# CRD42022306670.