https://www.sciencedaily.com/releases/2018/11/181105132939.htm

Screens are now a fixture of modern childhood. And as young people spend an increasing amount of time on electronic devices, the effects of these digital activities has become a prevalent concern among parents, caregivers, and policy-makers. Research indicating that between 50% to 90% of school-age children might not be getting enough sleep has prompted calls that technology use may be to blame. However, the new research findings from the Oxford Internet Institute at the University of Oxford, has shown that screen time has very little practical effect on children's sleep.

The study was conducted using data from the United States' 2016 National Survey of Children's Health. Parents from across the country completed self-report surveys on themselves, their children and household.