Excessive screen time in young children has been linked with developmental problems, but it has been difficult to disentangle cause and effect. While there is evidence that screen time limits opportunities for learning and growth, there is also evidence to suggest that children with developmental problems may receive more screen time to help manage difficult behaviors.
A study published January 28 in JAMA Pediatrics now provides some of the strongest evidence to date of a directional association between screen time and poor performance on development screening tests: toddlers who spent a greater amount of time watching TV or playing on a smartphone or computer than their peers were less likely to meet developmental milestones by age 5.
The researchers, led by Sheri Madigan, Ph.D., an assistant professor of psychology at the University of Calgary, did not observe the opposite to be true; toddlers who performed lower than expected on a developmental test did not end up having more screen time later.
Madigan and colleagues analyzed data from 2,441 children and their mothers who were part of the All Our Families Study. For this study, the mothers reported on their children’s screen time and completed the Ages and Stages Questionnaire (ASQ-3) at periodic intervals, including when the children were 24, 36, and 60 months of age. The ASQ-3 is a commonly used assessment that tracks progress in five developmental areas: communication, gross motor skills, fine motor skills, problem solving, and personal-social behavior.
The researchers used statistical methods to identify how screen time at one time point influenced ASQ-3 performance at the next time point and vice versa. As study co-author Dillon Browne, Ph.D., a family therapist and assistant professor of psychology at the University of Waterloo, explained to Psychiatric News, the researchers took great pains to adjust for all possible factors. This included differences between families that might also affect development, such as income and the parents’ education level, but also the natural changes within each child.
“Think of it like the growth charts pediatricians use to track height and weight,” Browne said. “Based on our data for each child, we could generate growth charts for their expected screen time and developmental performance at each interval. We found that if a child was using more media than should be expected at a certain age, then they would have a lower than expected ASQ-3 at the next assessment.”
Browne stressed that the reductions in ASQ-3 scores that followed excessive screen time were minor overall; screen time was not leading to dramatic developmental problems on average. “But this might be as close as we can get to showing causality using statistics,” he said.
Despite the significance of these findings, Browne said he believes it is preemptive to make sweeping clinical decisions based on the results. “Parents and physicians are always hungry for answers, but there is still a lot about the effects of screen time that we do not know,” he said.
One of the most pertinent questions in Browne’s opinion is what environmental conditions modify the potential consequences of screen time. “Is too much screen time worse for kids who are already a little behind when they hit 2 years old? Does it affect children with social anxieties more or less than their peers?” he asked. Another factor this study did not address was the type of screen activities, so future research needs to explore differences between passive activities such as watching television and active ones such as video games.
Understanding factors that may modify the risk of screen time on child development may help to identify children at most risk of developmental delays, but even then, Browne cautioned that there is no “one-size-fits-all” cutoff in terms of too much screen time. He thinks that the guidelines of both the American and Canadian pediatric associations—which recommend no more than one hour of quality screen programming per day—are a good benchmark, but he also appreciates that all children and families are unique.
The All Our Families Study is supported by a grant from Alberta Innovates Health Solutions. This study received additional research support from the Alberta Children’s Hospital Foundation and the Canada Research Chairs program. ■
“Association Between Screen Time and Children’s Performance on a Developmental Screening Test” can be accessed
here.