STUDY: Cell phones and screens keeping kids awake

These days, teachers often face classrooms filled with yawning students who stayed up late snapping selfies or playing online games.

For children and teens, using cell phones, tablets and computers at night is associated with losing sleep time and sleep quality, new research finds. Even children who don't use their phones or the other technologies littering their bedrooms at night are losing shut-eye and becoming prone to daylight sleepiness, the analysis published today in JAMA Pediatrics finds.

The analysis found "a consistent pattern of effect across a wide range of countries and settings," said Dr. Ben Carter, lead author and a senior lecturer in biostatistics at King's College London.

Carter and his colleagues weeded through the medical literature to identify hundreds of applicable studies conducted between January 1, 2011, and June 15, 2015. They chose 20 research reports involving a total of 125,198 children, evenly divided by gender, with an average age of 14 years. After extracting pertinent data, Carter and his co-authors performed their own meta-analysis.

Few parents will be surprised by the results: The team found a "strong and consistent association" between bedtime media device use and inadequate sleep quantity, poor sleep quality and excessive daytime sleepiness.

Surprisingly, though, Carter and his team discovered that children who did not use their devices in their bedrooms still had their sleep interrupted and were likely to suffer the same problems. The lights and sounds emitted by the technology, as well as the content itself, may be too stimulating.

Though Carter admits that a weakness of the analysis was "how the data was collected in the primary studies: self-reported by parents and children," many of us will probably recognize our own families' habits reflected in the statistics.