A world-first randomized controlled trial (RCT) of young children’s screen time shows that reducing screen time in the hour before bedtime improves the quality of young children’s sleep.

Screen Use in Young Children

It is well established that poor sleep in early childhood is associated with negative outcomes such as health problems, developmental difficulties and behavioral problems. The Nuffield Foundation-funded study, ‘Bedtime Boost’, is the first RCT to support paediatric guidelines on limiting young children’s screen time at bedtime. Researchers from the University of Bath, University of the Arts London (UAL), Birkbeck, Queen Mary University of London and King’s College London recruited families with 16- to 30-month-old toddlers from across London.

Of these, 105 families who already used screens with their child at bedtime were randomly assigned to either the intervention – parents were asked to eliminate screen time in the hour before bedtime and instead a bedtime box of non-screen-based activities (e.g., soothing play, reading, or puzzles) over a seven-week period – or the control conditions with appropriate activities but no mention of screen time. The toddlers’ sleep was recorded before and after the intervention using a portable motion sensor.

Parents in the intervention group were able to successfully reduce their toddlers’ screen time at bedtime, and the toddlers’ sleep quality improved, with more efficient nighttime sleep and fewer nighttime awakenings. Professor Rachael Bedford, who led the research at the University of Bath and is now head of the Queen Mary Child Development Lab and co-leader of the project, said: “We worked closely with parents and early years practitioners to ensure that the Bedtime Boost intervention was low-cost and easy to implement. The results suggest that the study was highly feasible for parents, with all intervention families completing the study. However, further research is needed to understand how changing the way families use screen media may influence these effects.

According to study leader Professor Tim Smith of the UAL Creative Computing Institute, previous correlational studies have shown that the more time toddlers spend in front of screens, the worse their sleep. However, it was not possible to know whether screen use caused sleep problems or vice versa. The Bedtime Boost study provides the first preliminary evidence that eliminating screen use from toddlers’ bedtime routines can lead to better sleep. Further work is needed to replicate these effects in a larger number of families.

Screen Time and Concussion

But can screen time also have a positive influence on children? Previous research has shown that screen time can slow children’s recovery from concussions, but new research from UBC and the University of Calgary suggests that banning screen time is not the answer. Researchers examined the associations between self-reported screen time in more than 700 children aged 8 to 16 years in the first 7 to 10 days after an injury and the symptoms reported by them and their caregivers in the following six months. The children whose concussion symptoms resolved most quickly had spent a moderate amount of time in front of the screen. “We call this group the ‘Goldilocks’ group because it seems that too little or too much screen time is not ideal for recovering from concussion,” said Dr. Molly Cairncross, an assistant professor at Simon Fraser University who conducted the study as a postdoctoral fellow with associate professor Dr. Noah Silverberg in the UBC psychology department. The results show that the common recommendation to avoid smartphones, computers and televisions as much as possible may not be best for children.”

The study was part of a larger project to study concussions called Advancing Concussion Assessment in Pediatrics (A-CAP), led by psychology professor Dr. Keith Yeates at the University of Calgary and funded by the Canadian Institutes of Health Research. The data came from participants aged 8 to 16 years who had either suffered a concussion or an orthopedic injury such as an ankle sprain or arm fracture and were treated in one of five emergency rooms in Canada. The purpose of including children with orthopedic injuries was to compare their recovery with the group that had suffered a concussion.

Patients in the concussion group generally had relatively worse symptoms than their orthopedic injury counterparts, but within the concussion group, it was not simply a matter of worsening symptoms with increasing screen time. Even children with minimal screen time recovered more slowly. Children use smartphones and computers to keep in touch with their peers. Completely avoiding these screens could therefore lead to feelings of isolation, loneliness, and a lack of social support. According to the researchers, these factors have a negative impact on children’s mental health, which can delay recovery.

The UBC/Calgary study differed from another study in that it tracked screen time and recovery over a longer period of time. The earlier study found that screen time slowed recovery, but it only measured screen use for the first 48 hours and symptoms for only 10 days. The longer time frame led to another interesting finding. Screen time during the early recovery phase had little impact on long-term health outcomes. At 30 days, children who had suffered concussions or other types of injuries reported similar symptoms regardless of their early screen use. The researchers also found that screen time appeared to have less of an influence on symptoms than other factors such as the patient’s gender, age, sleep habits, physical activity, or pre-existing symptoms. Ultimately, the results suggest that blanket restrictions on screen time for children and adolescents with concussion may not be helpful. Instead, the researchers suggest taking the same approach as with other activities, namely moderation. If symptoms flare up again, screen time can always be limited.