Prevalence, correlates, and trajectory of screen viewing among Chinese children in Changsha: a birth cohort study

High screen viewing time has detrimental effects on children's health, development, and behavior developing. Children are being exposed to more and more media devices at an earlier age. This study was aimed to determine the amount of daily screen time and its variation and to assess potential factors of screen time by identifying the trajectory of screen time among children aged 1 to 5 years.

This study was based on a representative sample of Changsha young children from a cohort study during 2015-2020. The demographic information and children's screen viewing time were collected by parents or caregivers through face-to-face interviews. The Latent growth model was used to test the effects of outdoor play on screen viewing time at eight time points, meanwhile, unconditional and conditional models were examined sequentially.

After excluding respondents with missing key variables, we included 953 children in the final analysis. Children's outdoor play was slightly increased at 18 months and subsequently declined at 24-60 months, with a maximum duration of 2.96 h per day. Children's average screen time was increased at 18-36 months, and decreased at 42-54 months, with a slight increase at 60 months. The duration of media exposure peaked at 1.4 h/d at age of 36 months and 60 months. Standardized coefficients of the outdoor play at age of 12 months showed negative effects on the screen time in children, but with positive influence at age of 24, 36, and 42 months (P <  0.01).

High proportions of young Chinese children in Changsha had more screen time than the AAP recommended according to our analysis. Significant predictors of screen time included pregnancy computer use, paternal educational level, and outdoor play in this study, however, further understanding of risk factors is needed to promote great public health efforts to reduce children's screen exposure.