Children who spend more time on digital media and screens at ages 24 and 36 months are more likely to have worse scores on developmental screening tests at ages 36 and 60 months, new data show.
“The results confirm the well-established link between increased screen time in young children and poorer developmental outcomes. What they add is a time course: the bump in screen time precedes the fall in developmental scores. This finding suggests that the screen time is actually the cause of the developmental delays and not the other way around,” David L. Hill, MD, FAAP, program director of the American Academy of Pediatrics Council on Communications and Media, told Medscape Medical News.
The researchers conducted a longitudinal cohort study using a three-wave, cross-lagged model to determine the directional association between screen time and child development among 2441 mother-child pairs. Participants were part of the longer All Our Families study, which recruited pregnant women between 2008 and 2010 and followed them and their offspring for 60 months.
For the current analysis, Madigan and colleagues analyzed data collected when the children were aged 24, 36, and 60 months. At those times, the mothers completed the Ages and Stages Questionnaire, Third Edition (ASQ-3). The ASQ-3 is a 30-item questionnaire that assesses developmental progress in communication, gross motor, fine motor, problem solving, and personal-social skills. The analysis included mothers who completed questionnaires on at least one point when the child was 24, 36, or 60 months old.
The researchers found a significant association between higher levels of screen time at ages 24 and 36 months and poorer performance on developmental screening tests at ages 36 months (β, −0.08; 95% confidence interval [CI], −0.13 to −0.02) and 60 months (β, −0.06; 95% CI, −0.13 to −0.02), respectively.
“Results suggest that screen time is likely the initial factor: greater screen time at 24 months was associated with poorer performance on developmental screening tests at 36 months, and similarly, greater screen time at 36 months was associated with lower scores on developmental screening tests at 60 months,” the authors write. “The obverse association was not observed.”
Person-level mean scores on the ASQ-3 were higher for girls and children whose mothers reported lower depression and higher household income, maternal positivity, child physical activity levels, child reading exposure, and hours of sleep each day. These predictors explained 15% of the variance.
Person-level mean amounts of screen time were lower for girls and children whose mothers reported lower maternal depression and higher levels of income, education, child reading exposure, and hours of sleep each night. These predictors explained 12% of the variance.
“When these variables were included, the standardized covariance (correlation) of the between-person stability factors was σ = −0.13 (95% CI, −0.19 to −0.08), suggesting the existence of a stable association between screen time and the ASQ-3 that is not accounted for by these predictors,” the researchers write.
Screen time may limit a child’s opportunity to develop gross motor skills, form relationships, and interact with others, including their caregivers, all of which are essential for child development.
“Clinicians need to remind parents that young children have more time and opportunity to master important developmental milestones when they spend less time with electronic devices,” Hill explained. Hill, who was not involved in the current study, is also vice president of Cape Fear Pediatrics, North Carolina; adjunct assistant professor of pediatrics at the University of North Carolina School of Medicine, Chapel Hill; and executive committee member of the North Carolina Pediatric Society.
“Clinicians must start by exploring where screens fit into families’ lives. One family may use them because a child is disruptive and screens calm her down. Another may believe that their child needs screens to learn important skills. Once we know why parents use screens, then we can offer better alternatives,” he added.
One coauthor has received grants from the Alberta Childrens Hospital Foundation, Alberta Innovates Health Solutions, the MaxBell Foundation, CanFASD, and the Canadian Institutes for Health Research during the conduct of the study. The remaining authors and Dr Hill have disclosed no relevant financial relationships.
JAMA Pediatrics. Published online January 28, 2019.