摘要：Objectives. We examined independent and synergistic effects of school and neighborhood environments on preadolescent body mass index (BMI) to determine why obesity rates nearly double during preadolescence. Methods. Physical measures and health surveys from fifth and sixth graders in 12 randomly selected schools in New Haven, Connecticut, in 2009 were matched to student sociodemographics and school- and residential census tract–level data, for a total of 811 urban preadolescents. Key independent variables included school connectedness, neighborhood social ties, and school and neighborhood socioeconomic status. We estimated cross-classified random-effects hierarchical linear models to examine associations between key school and neighborhood characteristics with student BMI. Results. Greater average connectedness felt by students to their school was significantly associated with lower BMI. This association was stronger among students living in neighborhoods with higher concentrations of affluent neighbors. Conclusions. How schools engage and support students may affect obesity rates preferentially in higher-income neighborhoods. Further research should explore the associations between multiple environments to which children are exposed and obesity-related behaviors and outcomes. This understanding of the multiple social–spatial contexts that children occupy has potential to inform comprehensive and sustainable child obesity prevention efforts. Approximately 17% of the children in the United States aged 2 to 19 years are obese. 1 Obesity has both short- and long-term health consequences through adulthood. 2–5 A vast field of research has struggled to identify factors contributing to this epidemic that are most amenable to change. Recent research has used ecological frameworks to explore risks for childhood obesity at multiple levels, 6 including school 7 and neighborhood 8 contexts, yet few studies have explored these contexts simultaneously. 9–11 Despite the fact that obesity rates nearly double during preadolescence, 12 few studies have explored contextual effects specific to this age group. 13
