Effect of early screen media multitasking on behavioural problems in school-age children.

Screen media multitasking (SMM), the act of exposure ≥ 2 screen media simultaneously, is increasing nowadays. Single media use was associated with child's behavioural problems in previous studies. However, the associations between SMM since early childhood and behavioural problems in school-age children had not been elucidated. This study aimed to investigate the association between SMM from age 6 months to 4 years and behavioural problems in 6-year-old children. Two hundred and ninety-one (52.6% girls) healthy children were enrolled since age 6 months and 259 participants were followed-up until age 6 years. SMM was obtained at age 6, 12, 18, 24 months, 3 and 4 years. Behavioural concerns were assessed at age 4 years by the Child Behaviour Checklist and by both the Strengths and Difficulties Questionnaire with the Conners Kiddie Continuous Performance Test at age 6 years. Parenting style, cognitive ability, and baseline characteristics were also ascertained. Partial least squares path modelling was performed to determine both direct and indirect relationships among variables. Results showed that children who had been exposed to SMM for longer duration, specifically at age 18 months, showed more behavioural problems at age 4 and 6 years. Positive parenting during preschool and behavioural concerns at age 4 years were main mediators of those associations. Moreover, SMM in minutes at age 18 months was related to decreased preschool cognition. To minimise behavioural problems in school-age children, SMM should be avoided before 2 years of age so that positive parenting may be successfully implemented since early childhood.