Associations between screen time and mental health in childhood and adolescence: Findings from the Millennium Cohort Study

Objective: This study aimed to examine the curvilinear relationship between screen time and mental health in childhood and adolescence—thereby testing the digital Goldilocks hypothesis (Przybylski & Weinstein, 2017). Methods: Multiple data sweeps were utilised from the Millennium Cohort Study, a nationally representative longitudinal study of children born in the UK in 2000-2002. Mental health was assessed using the Strengths and Difficulties Questionnaire, focusing on internalising and externalising problems. Screen time was measured in hours per day for TV viewing and video gaming. Separate ordinary least squares regression analyses were conducted for each combination of measures of mental health and screen time at age 5, 7, 11, 14 and 17—controlling for ethnicity, gender, and neighbourhood deprivation. Results: A curvilinear relationship was found for age 14 (for both TV viewing and video gaming and for externalising and internalising problems), but findings across other ages were inconsistent. Data does indicate that both excessive screen time (7 hours or more), and none at all may adversely affect the mental health of children and adolescents. Conclusions: This study provides some evidence in support of the Goldilocks hypothesis across childhood and adolescence. It also provides valuable insights into the nuanced association between screen time and mental health, emphasising the need for further investigation. The findings suggest the importance of balanced screen time to mitigate potential negative impacts on mental health. Continued research in this area is crucial to inform evidence-based guidelines and promote healthy screen time use among children and adolescents.