RESUMO
BACKGROUND: Exposure to electronic media is increasing from early childhood. This study aimed to examine the association between screen time and behavioral outcomes in school-aged children with a prospective birth-cohort. METHODS: We examined the association between screen time and behavioral outcomes in school-aged children with a Korean birth-cohort study. Participants were 2,150 children, recruited during their fetal period, assessed annually for developmental outcomes. Media exposure was assessed at T4 (3.2 y/o), T8 (7.3 y/o), and T10 (9.4 y/o). After exclusions for missing data, 1,368 children were categorized into four groups (Low-Low, Low-High, High-Low, and High-High) based on average daily media time in early childhood and during schooldays, respectively. Children's temperament was assessed from T1 (0.5 y/o) to T4. Emotional and behavioral outcomes were assessed using the Child Behavior Checklist (DSM-oriented subscales) at T8 and T10. RESULTS: We found that early-years temperament was generally similar between the media-time groups: they only differed significantly on Activity at T1 and Emotionality at T2 (1.2 y/o). However, compared to the Low-Low group, the Low-High group had significantly higher odds of high-risk scores for Conduct Problems (increased odds ratios [ORs] of 1.82 at T8 and 1.83 at T10) and Anxiety Problems (increased ORs of 1.60 at T8 and 1.82 at T10). Self-rated self-esteem and overall happiness at T10 also significantly differed among the four groups. CONCLUSION: Our findings suggest the negative impacts of media exposure on the emotional and behavioral development of school-aged children, which substantiates the guidelines that restrict media exposure during childhood.