<![CDATA[Background: Adolescence is a developmental period characterized by heightened emotional and behavioral vulnerability, which may be influenced by increasing exposure to digital devices. Objectives: This study aimed to examine the association between age, gender, and duration of gadget use and mental health among adolescents. Methods: A school-based cross-sectional study was conducted among 69 twelfth-grade students aged 15–18 years at a vocational high school in Central Java, Indonesia, selected through accidental sampling. Mental health status was assessed using the Strengths and Difficulties Questionnaire (SDQ-18), while duration of gadget use was measured using a structured self-report questionnaire. Descriptive statistics were used to summarize participant characteristics. Associations were analyzed using Chi-square tests and multiple linear regression to identify independent predictors of emotional strength and behavioral difficulties. Results: High gadget use was significantly associated with abnormal emotional difficulties (93.8%) and lower emotional strength (87.5%). Bivariate analysis demonstrated significant associations between gadget use and mental health outcomes (p < 0.001) and between age and mental health (p = 0.027), whereas gender was not significantly associated (p = 0.117). In multivariate models, gadget use and emotional difficulties remained significant predictors (p < 0.05), explaining 81.2% of the variance in emotional strength (R² = 0.812) and 76.5% of the variance in behavioral difficulties (R² = 0.765). Conclusions: These findings indicate that greater duration of gadget use is associated with poorer mental health indicators among adolescents. Given the cross-sectional design, causal inferences cannot be established. Strategies promoting balanced digital use and school-based mental health support may help mitigate potential adverse outcomes.]]>
