Screen time and developmental and behavioral outcomes for preschool children.

International guidelines recommend that preschoolers spend no more than 1 h/day viewing screens. Research is needed to determine if there is a relation between screen time levels and child developmental and behavioral outcomes. Compared to ≤1 h/day, children viewing screens 2 or ≥3 h/day had an increased likelihood of behavioral problems, delayed achievement of developmental milestones, and poorer vocabulary acquisition. Findings highlight the association between duration of screen time and factors of child development.