Few longitudinal studies have assessed the association between screen viewing in pre-schoolers and its interference with sleep and sedentary behaviours.
The Growing Up in Singapore Towards healthy Outcomes (GUSTO) study recruited pregnant women (n=1,247) between 2009 and 2010, during their first ultrasound. Patient-reported information about children’s daily total and device-specific screen time were collected at age 2-3 years. At 5.5 years, children’s sedentary behaviour, light physical activity, moderate-to-vigorous activity and sleep were collected on seven consecutive days using wrist-worn accelerometers (n=552).
Total screen time at age 2-3 years had a statistically significant negative dose-related impact on sleep (OR 0·99; 95% CI 0·97-1·00), light physical activity (OR 0·97; 95% CI 0·96-0·99), and moderate-vigorous physical activity (OR 0·95; 95% CI 0·93-0·97) at age 5.5 years.
Trends were comparable between different devices; television, handheld devices, or computers. Greater than three hours of viewing per day on any device between 2-3 years of age was negatively associated with physical activity and sleep at age 5.5 years. No significant differences in time spent sleeping were observed between the device groups.
Screen time may displace physical activity during early childhood and reducing screen viewing may promote healthier behaviours and health outcomes later in life.