Supplementary Material for: DisConnect: Characterisation of screen use and perception of health problems in students from Aveiro, Portugal: a cross-sectional study

Introduction: Digitalization has made technologies an important vehicle for development and learning, especially for children and young people. However, multiple risks of excessive or inappropriate use have been described. This study aimed at characterising the use of screens in young Portuguese students and the association with perceived health problems in the Aveiro municipality.
Methods: A cross-sectional study was conducted between September 2019 and April 2020 to students enrolled in schools in the Aveiro municipality, through a questionnaire applied to 4th, 6th and 8th-graders. A descriptive analysis characterised the screen use, while logistic regressions assessed association with perceived health outcomes.
Results: Four of the 989 students who responded to the questionnaire (0.4%) reported not using any screen device. Around 57% reported not taking any device to school. Screen time spent during weekdays was associated with higher reduction on physical activity (adjOR=2.54, p=0.019). Receiving a device between 0-5 years old showed positive association with body pain (adjOR=1.62, p=0.034), and using screens at school was associated with more problems at home (adjOR=2.04, p=0.01). Screen use during meals and having screens in the bedroom during sleep were consistently associated with a more negative perception of health outcomes.
Discussion: Literature points to a multitude of possible health consequences regarding inadequate or excessive screen use, but most data is based on small samples and a limited number of observations. This is one of the first studies describing screen use among young school goers in Portugal, and the first using a big representative sample of Aveiro students. Our study gives some insight on the screen habits of young people, and demonstrates that some habits can have impact on important aspects such as physical activity, body pain and family dynamics.
Conclusion: Screen use and screen habits have important consequences in multiple aspects of health. Systematic data collection on screen use and its impact on health, including mental health, among school goers is essential, particularly to understand long-term effects and allow effective prevention strategies.