Abstract
AIM: To compare physical activity and screen time behaviour of Swedish youth between three pandemic phases using data from an annual survey, and to evaluate the feasibility of device-measured physical activity for future survey rounds. METHODS: A repeated cross-sectional study with data from a Swedish population-based survey (2018-2023) with questions on physical activity and screen time behaviour. The study period was categorised into prepandemic, pandemic and postpandemic phases. In 2022, screen time quality was included and a subsample used accelerometers (n = 700). RESULTS: A total of 50 163 children and adolescents (4-17 years) were included (49.0% girls, mean age 10.2 years). Regression models showed that physical activity was higher before (unstandardised B [95% CI] = 0.057 [0.002-0.112]) and after (0.046 [-0.004; 0.095]) the pandemic. Screen time was lower prepandemically (OR [95% CI] = 0.759 [0.726; 0.794]), with no significant difference during and after the pandemic. Data from 94% of the accelerometers were obtained, and these participants had higher socioeconomic status compared with the survey population. CONCLUSION: Screen time increased during COVID-19 and remained high after, while physical activity levels seemed less affected by the pandemic phases. Future studies would benefit from screen time quality assessment and complementary device-based physical activity measurements.