Whether high quantities of center-based care cause behavior problems is a controversial question. Studies using covariate adjustment for selection factors have detected relations between center care and behavior problems, but studies with stronger internal validity less often find such evidence. We examined whether within-child changes in hours in…

Object exploration is considered a driver of motor, cognitive, and social development. However, little is known about how early childhood education and care settings facilitate object exploration. This study examined if children's exploration of objects during free play was facilitated by the use of particular spatial components (floor, tables,…

This study aimed to determine the effects of the Active Early Learning (AEL) childcare center-based physical activity intervention on early childhood executive function and expressive vocabulary via a randomized controlled trial. Three-hundred-and-fourteen preschool children (134 girls) aged 3-5 years from 15 childcare centers were randomly…

Although professional development is widely used to improve the impacts of early childhood education, little is known about the conditions under which such interventions promote child outcomes. This study applies newly developed methods for quantifying intervention impact heterogeneity to understand whether educators' collective workplace stress…