Objective. To investigate the correlations among screen time,outdoor activity time,and the physical health of preschoolers,so as to provide suggestions for formulating interventions to prevent myopia and obesity of children.Methods A cross-sectional study was carried out in Shenzhen city. A representative sample of 5 226 preschoolers and their caregivers were recruited by a proportional stratified cluster sampling. Data were collected by the Chinese early human capability index( CHe HCI),children's media use in daily family life questionnaire,and body mass index( BMI). Linear regression and binary Logistic regression models were used to analyze the effects of screen time and outdoor activity time on physical health of preschoolers.
Results. Preschoolers spent( 110. 30±90. 67) min/d on screen and( 61. 11±41. 16) min/d on outdoor activity. And 5. 47% of preschoolers were overweight. Screen time negatively predicted preschoolers ' physical health,while outdoor activity time positively predicted preschoolers ' physical health of CHe HCI. There was no significant association between outdoor activity time and overweight of preschoolers.
Conclusion. This study suggests parents might need to reduce preschoolers' screen time and increase outdoor activity time to promote the physical health development of preschoolers.