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Bedtime Electronic Devices (BED)

The BED study aims to understand how the use of electronic media (screens), both before and in-bed, affects sleep and mental health of young adolescents. We are also interested in how this bedtime electronic media use might impact dietary intake the next day.

We have discovered that not getting enough high-quality sleep is a crucial risk factor for obesity in children. With more than a third of New Zealand's children and adolescents being overweight or obese, it is important to investigate the role of screen use on sleep and subsequent dietary intake.

Streaming rather than dreaming: are electronic media and bed a good mix for children?

The use of screens in bed has become commonplace. Studies looking at the influence that children's screen use in bed has on their sleep quality has been hindered by previously poor measurement of screen use and sleep, and by the use of study designs that don't allow these influences to be clearly attributed to the outcomes measured.

The BED study's goal was to address many of the limitations in the existing research evidence. We aimed to accurately and objectively measure screen use throughout the night, including the times when parents may not be aware that children are using devices! With our longitudinal, repeated measures design, we can explore how evening screen use might influence sleep during the night, and affect dietary intake, mood, wellbeing and physical activity levels during the day.

Using technology to measure device use

Over an seven-day period, children (aged 11-14yrs) wore an accelerometer 24-hours-a-day to measure sleep, physical activity, and sedentary time. The study collected evening and night-time footage using wearable and stationary video cameras (over four nights), as well as dietary intake data on three days. In addition, the team developed a new questionnaire, which aims to determine the reliability and validity of self-reported sleep timing and screen use before and in-bed, along with an evening questionnaire measuring mood and well-being.

Our novel research approach has the potential to accurately measure the effect of screen behaviours on key outcomes, such as same-night sleep and next-day mood, wellbeing, eating and activity. The results from this study will provide more specific policy advice and guidance surrounding the bedtime use of electronic media by children.

BED Study in the news

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