Introduction: Electronic devices in the bedroom are broadly linked with poor sleep in adolescents. This study investigated whether there is a dose-response relationship between use of electronic devices (computers, cellphones, televisions and radios) in bed prior to sleep and adolescent sleep patterns.
Methods: Adolescents aged 11-17 yrs (n = 1,184; 67.6% female) completed an Australia-wide internet survey that examined sleep patterns, sleepiness, sleep disorders, the presence of electronic devices in the bedroom and frequency of use in bed at night.
Results: Over 70% of adolescents reported 2 or more electronic devices in their bedroom at night. Use of devices in bed a few nights per week or more was 46.8% cellphone, 38.5% computer, 23.2% TV, and 15.8% radio. Device use had dose-dependent associations with later sleep onset on weekdays (highest-dose computer adjOR = 3.75: 99% CI = 2.17-6.46; cellphone 2.29: 1.22-4.30) and weekends (computer 3.68: 2.14-6.32; cellphone 3.24: 1.70-6.19; TV 2.32: 1.30-4.14), and later waking on weekdays (computer 2.08: 1.25-3.44; TV 2.31: 1.33-4.02) and weekends (computer 1.99: 1.21-3.26; cellphone 2.33: 1.33-4.08; TV 2.04: 1.18-3.55). Only 'almost every night' computer use (: 2.43: 1.45-4.08) was associated with short weekday sleep duration, and only 'almost every night' cellphone use (2.23: 1.26-3.94) was associated with wake lag (waking later on weekends).
Conclusions: Use of computers, cell-phones and televisions at higher doses was associated with delayed sleep/wake schedules and wake lag, potentially impairing health and educational outcomes.