Longitudinal associations between screen time and children's behavioural and emotional adjustment at age 7

Abstract

Background and objectives: Research on whether children’s screen time impacts on their adjustment mainly focuses on television (TV) use, and seldom considers more interactive forms of screen entertainment such as computers. Longitudinal population studies suggest negative effects of high TV use in young children on externalising behaviour including aggres- sion and attentional problems. However, evidence (particularly for inattention/hyperactivity) is mixed and timing of exposure may be critical. Existing UK studies of effects of screen time on young chikdren are cross-sectional. Objectives: To investigate whether heavy TV and computer use in early childhood predict behavioural and emotional adjustment at age 7 Methods: Data came from 11 014 children in the UK Millennium Cohort Study. Mothers reported child’s daily TV use at ages 3 and 5, using four-point and six-point scales respectively. Children were divided into four groups: ‘sustained low’(< 3 h Abstracts daily at 3 and 5 years), ‘sustained high’ (3+ h daily at 3 and 5 years), ‘increasing’ (< 3 h at 3, 3+ h at 5 years) and ‘decreasing’ (3+ h at 3, <3 h at 5 years). Computer use was reported by mothers using a six-point scale at age 5, and divided into ‘low’ (<3 h) or ‘high’ (3+ h). Teachers reported adjustment using the Strength and Diffi culties questionnaire when children were aged 7. Multivariate analyses of conduct problems, emotional symptoms, peer problems, inattention/hyperactivity, total diffi culties and prosocial behaviour controlled for socio-de- mographics; maternal health; family functioning; and child’s sleeping diffi culties, physical activity, cognitive ability and rel- evant prior adjustment score. Results: At ages 3 and 5, respectively 17% and 15% watched TV for more than 3 h daily. 73% had sustained low, 5% sus- tained high, 10% increasing and 12% decreasing use. At age 5, 2% used computers for more than 3 h daily. In adjusted mod- els, increasing TV use was associated with conduct problems (β 0.18, 95% CI 0.06 to 0.30, p =0.003) and total diffi culties (β 0.49, 95% CI 0.04 to 0.95, p=0.035). Decreasing TV use was associated with lower inattention/hyperactivity (β −0.21, 95% CI −0.39 to −0.04, p=0.019). High computer use was associated with emotional symptoms (β 0.37, 95% CI 0.09 to 0.64, p=0.009). Associations with peer problems and proso- cial behaviour were not signifi cant. There were no signifi cant interactions between gender and screen time. Conclusion: Patterns of TV and computer use are associated with some adjustment problems in young children, signalling the need to restrict hours of exposure for this age group.