title: A multi-level examination of the association between older social models in the school environment and overweight and obesity among younger students.
abstract: Few studies have examined how school characteristics are associated with obesity. The purpose of this study was to examine the student- and school-level characteristics associated with being overweight and obese among 12,049 students in grades 9 and 10 (junior students) attending 76 secondary schools in Ontario, Canada. The sample was 49.2% female and the average age was 14.7 years. Overall, 15.0% of the sample was considered overweight and 6.3% of the sample was considered obese. Multi-level regression analysis revealed significant between-school random variation for the likelihood of a junior student (grade 9 or 10) being overweight or obese. For each 1% increase in the prevalence of obese senior students (grade 11 and 12) at a school, the odds of a junior student at that school being overweight or obese increased significantly. Important student-level characteristics included physical activity, screen time sedentary behaviour (e.g., watching television), participation in varsity sports and gender. Future research should evaluate if the optimal population level impact for school-based obesity prevention programming might be achieved by targeting the schools that are putting students at the greatest risk.
authors.affiliation: Department of Population Studies and Surveillance, Cancer Care Ontario, 620 University Avenue, Toronto, Ontario, Canada. scott.leatherdale@cancercare.on.ca
authors.forename: Scott T
authors.initials: ST
authors.lastname: Leatherdale
authors.forename: Sophia
authors.initials: S
authors.lastname: Papadakis
mesh_terms: D000293:Adolescent; D000367:Age Factors; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007398:Interpersonal Relations; D008297:Male; D009043:Motor Activity; D015999:Multivariate Analysis; D009765:Obesity / Q000453:epidemiology* / Q000523:psychology; D009864:Ontario; D050177:Overweight / Q000453:epidemiology* / Q000523:psychology; D015995:Prevalence; D012574:Schools; D057185:Sedentary Behavior; D057566:Self Report; D012907:Smoking / Q000453:epidemiology; D012931:Social Environment; D013334:Students / Q000706:statistics & numerical data*