Research identifies impact of teenage screen use

Two-thirds of children use more than one screen at the same time after school, in the evenings and at weekends as part of increasingly sedentary lifestyles, according to a new study led by a researcher at the University of Strathclyde.

The study of more than 800 adolescent girls between the ages of 11 and 14 identified worrying trends between screen use and lower physical activity – including higher BMI (body mass index) – as well as less sleep.

The use of concurrent screens - termed ‘screen stacking’ - grew over the course of the week, with 59% of adolescents using two or more screens after school, 65% in the evenings, and 68% at weekends. Some teenagers reporting using as many as four screens at one time.

But further analysis showed the use of any screen was still detrimental to the indicators of health and wellbeing. More than 90% owned or had access to a smart phone and using this after school had a knock-on effect on their sleep.

The study, published in the journal Acta Paediatrica, was led by Dr Deirdre Harrington, now of Strathclyde’s School of Psychological Sciences and Health, during her time at the University of Leicester. She said: “Intuitively, we believe there must be negative effects on teenagers of using too many screens at the same time. Our data show it isn’t as simple as that.

“This research was done before the COVID-19 lockdown, where much more of our day is spent in front of a screen. More than ever the effects of this on adolescents need to be known – there are positives too, no doubt.

“These adolescents wore an accelerometer 24 hours a day for a week allowing us to capture their daily routines and even estimate their sleep. Uniquely, they also reported how many screens they used at the same time, which is not well known.”

Researchers from Leicester’s Diabetes Research Centre measured physical activity and sleep using accelerometers worn on participants’ wrists, while those involved in the study self-reported the number of screens they were using at the same time – such as scrolling on a mobile phone while also watching TV – as well as perceptions of self-esteem and physical self-worth.

Dr Harringron said: “My focus will continue to be on young people and families in my new role at Strathclyde. I am already linking up with research groups with strengths in 24-hour movement behaviour measurement and behaviour change.

“My first piece of research will be with pre-schoolers whose sleep, physical activity and screen time have been impacted by lockdown disruptions. I am keen to work with groups and organisations all over Scotland who make decisions on the education and health of pre-schoolers and their caregivers too. They can help shape our new research.”

The study was supported by the National Institute for Public Health Research programme as well as the NIHR Leicester Biomedical Research Centre, and the NIHR Applied Research and Care (ARC) East Midlands.