Dataset: Screen time, social media use, physical activity and depressive symptoms (CDI) in Brazilian schoolchildren (n = 320)

This dataset contains de-identified data from a cross-sectional study conducted between 2024 and 2025 including 320 schoolchildren aged 7–14 years. The study evaluated associations between daily screen time, social media use, physical activity, and depressive symptoms measured using the Children’s Depression Inventory (CDI). The dataset includes sociodemographic variables (age, school year, household arrangement), behavioral exposures (daily screen time in minutes, social media use, weekly frequency of physical activity), and mental health outcomes (CDI total score and categorized cut-offs ≥13 and ≥17). Logistic regression models (CDI ≥13 and ≥17) and linear regression models (continuous CDI score) were used to estimate associations. Correlation analyses between screen time and continuous CDI score are also supported by the dataset. All personal identifiers were removed prior to data sharing. The dataset complies with ethical standards and approved research protocols.