Prevalence, correlates and mental health outcomes of Internet addiction among Chinese adolescents across early, middle and late adolescence.

OBJECTIVE: Although there is a growing awareness of the age differences in adolescent Internet addiction (IA), comparative research exploring the prevalence and correlates of IA across distinct developmental stages remains limited among Chinese adolescents. This study aimed to investigate the IA prevalence and its associations with demographics, lifestyles, psychosocial factors and mental health outcomes among Chinese adolescents from early to late adolescence. METHODS: A total of 67,182 adolescents from Shenzhen, China participated in this cross-sectional online survey, completing self-reported questionnaires that assessed demographics, lifestyles, psychosocial factors, IA and mental health problems. RESULTS: The prevalence of IA was 2.7 %, 3.4 % and 6.0 % in early, middle and late adolescence, showing a progressive increase with advancing developmental stages. Grade, single child status, parental marital status and family history of mental disorders showed age-specific association patterns with adolescent IA, while gender, exercise frequency, habits of smoking or drinking, stressful life events and resilience demonstrated consistently significant associations with IA across all developmental stages. After adjusting for all covariates, IA exhibited significant associations with increased risks of depression, anxiety and suicidal ideation, except for anxiety in late adolescence. Notably, different association patterns emerged between IA and sleep disturbance across different developmental stages. CONCLUSIONS: These findings underscore a progressive age-related increase in IA prevalence and reveal distinct correlates of IA across different stages of adolescence, providing nuanced insights into developing targeted prevention and intervention strategies for adolescent IA.