Determinants of smartphone addiction and its association with psychological morbidity among school-going adolescents in Karaikal, Puducherry, India: a cross-sectional study

The unprecedented surge in smartphone utilization among Indian adolescents has raised significant public health concerns regarding behavioral addictions and mental well-being. To identify determinants of smartphone addiction and examine its association with psychological morbidity among school-going adolescents in Karaikal, Puducherry, India. A facility-based, cross-sectional study was conducted between September 2025 and February 2026, encompassing 645 students (grades 6–10) selected via multistage random sampling. Data were collected using self-administered questionnaires, including the Smartphone Addiction Scale-Short Version (SAS-SV) and the General Health Questionnaire-12 (GHQ-12). Determinants were analyzed using univariate and multivariate logistic regression in SPSS. The prevalence of smartphone addiction was 28.5% (95% CI: 25.0–32.0%), while 26.0% of participants had psychological morbidity. After adjustment for potential confounders, smartphone use for ≥1 h before bedtime (AOR = 2.233; 95% CI: 1.325–3.761), weekend smartphone use for ≥2 h (AOR = 1.939; 95% CI: 1.297–2.897), engagement in regular outdoor activities (AOR = 1.619; 95% CI: 1.060–2.472), and psychological morbidity (AOR = 1.829; 95% CI: 1.223–2.736) were independently associated with smartphone addiction. Sleeping ≥ 6 h per night was independently associated with lower odds of smartphone addiction (AOR = 0.456; 95% CI: 0.219–0.947). Smartphone addiction affects more than one-quarter of school-going adolescents and is significantly associated with psychological morbidity. Prolonged bedtime smartphone use, excessive weekend screen time, and inadequate sleep were important modifiable determinants.