Background: Time spent on screens and adiposity change rapidly from childhood to adolescence, with differences by gender and race/ethnicity.
Objective: Apply time-varying effect models (TVEMs) to a nationally representative sample of youth to identify the age ranges when the cross-sectional associations between television viewing, computer use, and adiposity are significant.
Methods: Data from 8 to 15-year-olds (n = 3593) from the National Health and Nutrition Examination Survey (2011-2018) were extracted. TVEMs estimated the associations between television viewing, computer use, and fat mass index as dynamic functions of the participants' age, stratified by gender and race/ethnicity.
Results: TVEMs revealed age-specific statistically significant associations that differed by gender and race/ethnicity. Notably, computer use was related to higher adiposity in non-Hispanic White females aged 9.3-11.4 years (slope β-range: 0.1-0.2) and in non-Hispanic Black females older than 14.8 years (β-range: 0.1-0.5). In males, these age windows were 13.5-15.0 years (non-Hispanic White, β-range: 0.1-0.2), 11.4-13.0 years (non-Hispanic Black, β-range: 0.1-0.14), and older than 13.0 years (Hispanic, β-range: 0.1-0.4).
Conclusions: More research during the specific age ranges in the demographic subgroups identified here could increase our understanding of tailored interventions in youth.
Keywords: adolescents; body composition; children; obesity; screen time; sedentary behaviour.
© 2023 World Obesity Federation. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.