Early childhood screen time as a predictor of emotional and behavioral problems in children at 4 years: a birth cohort study in China

BACKGROUND: Previous studies have suggested that screen time (ST) has a negative effect on children’s emotional and behavioral health, but there are few longitudinal studies that have been conducted with infants and toddlers. This study sought to examine the effect of ST in early childhood on emotional and behavioral problems in children aged 4 years, based on a birth cohort study in China. METHODS: A total of 2492 children aged 4 years were enrolled in this study. The parents and guardians of each child completed a questionnaire that included items eliciting information on children’s birth information, socio-demographic information at baseline, and ST at each follow-up. Emotional and behavioral problems were assessed using the Strengths and Difficulties Questionnaire (SDQ) at 4 years of age. Multivariate logistic analysis was used to explore the effects of ST on emotional and behavioral problems. RESULTS: The percentages of children with ST > 0 h/day at age 0.5 years, ST > 2 h/day at age 2.5 years, and ST > 2 h/day at age 4 years were 45.7, 55.5, and 34.5% respectively. The prevalence of emotional and behavioral problems was 10.8%. ST at 6 months was a risk factor for emotional symptoms and hyperactivity at the age of 4 years. ST at age 2.5 years was a risk factor for hyperactivity at the age of 4 years. However, ST at age 4 years was a risk factor for total difficulties, conduct problems, peer problems, hyperactivity, and prosocial behavior. CONCLUSIONS: Higher ST exposure at early childhood is associated with later emotional and behavioral problems. In particular, sustained high ST exposure is a risk factor for behavioral problems. These findings suggested the importance of controlling ST to prevent the occurrence of emotional and behavioral problems in the early years. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12199-020-00926-w.