Sleep duration moderates association between screen time and emotional and behavioural problems in young children

Preschoolers and young children are vulnerable to psychosocial and behavioral disorders linked to lifestyle factors such as screen time and sleep disturbances. Our study examines the relationship between screen time and adherence to recommendations with children's behavioral and emotional difficulties, with a focus on the role of sleep duration.

Cross-sectional analyses were conducted within the multicenter prospective Childhood Obesity Risk Assessment Longitudinal Study (CORALS), which included 1420 children aged 3-6 years. Screen time (hours/day) and adherence to recommendations (≤ 2 hours/day) were assessed. Behavioral and emotional difficulties were measured via the strengths and difficulties questionnaire. Multivariable linear and logistic regression models were used to estimate associations between screen time (continuous and dichotomous) and strengths and difficulties questionnaire scores, adjusting for potential confounders. We also tested the moderating effect of sleep and conducted isotemporal substitution analyses replacing screen time with sleep duration.

Higher screen time was associated with higher total strengths and difficulties questionnaire scores [β 95% confidence interval (CI), 0.35 (0.10, 0.61)], emotional symptoms [0.10 (0.01, 0.19)], conduct problems [0.10 (0.01, 0.18)], and greater odds of exceeding the 16-point strengths and difficulties questionnaire cutoff for behavioral and emotional difficulties [odds ratio (OR) (95% CI), 1.21 (1.04, 1.41)]. Children who adhered to screen time recommendations had lower strengths and difficulties questionnaire total scores [β (95% CI), - 0.64 (- 1.19, - 0.10)] and odds of experiencing behavioral and emotional difficulties [OR (95% CI), 0.67 (0.47, 0.95)]. Sleep duration moderated the screen time-strengths and difficulties questionnaire association (P = 0.020). The isotemporal substitution of screen time for sleep duration was associated with lower strengths and difficulties questionnaire scores across all subscales, except for prosocial behavior.

Higher screen time was associated with greater emotional and behavioral difficulties, whereas adherence to screen time recommendations and adequate sleep duration were inversely associated. Managing screen time and promoting sleep are crucial for children's well-being.