Executive dysfunction as a possible mediator for the association between excessive screen time and problematic behaviors in preschoolers.

Excessive screen time in children is a growing concern for parents and healthcare providers worldwide because it frequently leads to behavioral problems. Although executive dysfunction is proposed to be one of the contributing factors to maladaptive behaviors, little is known about the link between screen time and behaviors. This study aimed to identify whether executive dysfunction contributes to the negative behaviors of children exposed to excessive screen time. A cross-sectional study was conducted on preschool-aged children from public and private schools in Chiang Mai, Thailand. The parents/guardians of each child completed the questionnaires regarding clinical characteristics and screen time use, the Behavior Rating Inventory for Executive Function-Preschool (BRIEF-P), and the Strengths and Difficulties Questionnaire (SDQ). Children with more than one hour of media exposure per day were considered to have excessive screen time. Multivariable Gaussian regression was analyzed to compare the BRIEF-P and SDQ scores between the excessive and appropriate screen time groups. Causal mediation analysis was performed to examine the effects of total screen time on increasing behavioral problems with executive functioning as a mediator. A total of 1,126 preschoolers were included in the analyses. After controlling for age, sex, socioeconomic status, and maternal education, the excessive screen time group had significantly higher BRIEF-P global executive composite score than the appropriate screen time group (mean difference of global executive composite score = 1.49, 95% CI [0.12, 2.86], and p = 0.033). Concurrently, there were significant differences in externalizing behavior subscales and SDQ total difficulties scores between the excessive and appropriate screen time groups (mean difference of total difficulties score = 0.90, 95% CI [0.29, 1.50], and p = 0.004). A significant average causal mediation effect (ACME) of screen time on behavioral problems mediated through executive functioning was β = 0.28, 95% CI [0.13-0.44], which was more than half of the total effect (54.9%, 95% CI [37.4-100%]). The current study suggests that the increase in behavioral issues in preschoolers might be partly explained by the direct effect of excessive screen time and the mediating effect of impaired executive functioning. Our results may raise concerns about the necessity to limit screen time and monitor for executive function deficits and behavioral problems in young children with high screen time.