Gabrielle Garon-Carrier

Objective: The aim of this study was to assess the developmental risks associated with total screen time, and specifically newer mobile devices, in the context of the pandemic. Methods: This study uses parent-reported data from a prospective cohort of Canadian preschool-age children. The exposure variable is child daily screen time measured at the age of 3.5 years categorized as light (<1 hr/d), moderate (1–4 hr/d), or intensive (>4 hr/d) use (N = 315). Time spent on mobile devices was considered separately as a continuous variable. Our outcome is child global development scores, which combine assessments of communication, cognitive, personal-social, and motor skills measured at the age of 4.5 years using the Ages and Stages Questionnaire (ASQ) (N = 249, 79% retained). ASQ scores were dichotomized to distinguish children at risk of developmental delays (below the 15th percentile) from those not at risk. We estimate associations between child screen time and later global development using multiple regressions adjusted for child sex and temperament, and parent education. We also examine whether associations are moderated by child and parent characteristics. Results: Logistic regressions revealed that intensive users were more at risk of global developmental delays compared with light users (OR = 4.29, p = 0.020). Mobile device use was also associated with lower global scores (β = −3.064; p = 0.028), but not with risk of delays. We found no evidence that associations were moderated by child sex and temperament, or parent education. Conclusion: The findings suggest that intensive screen time may be associated with delays in child global development. Early childhood professionals should encourage families with preschoolers to prioritize screen-free activities to promote optimal cognitive, language, social, and motor development.