The Laurie M. Tisch Center for Food, Education & Policy
This study, published in Health Education & Behavior, takes baseline data from the Food, Health & Choices project, with 5th graders in 20 New York City public schools, and determined that obesity rates, eating behaviors and theory-based psychosocial determinants were more similar within schools than across different schools, even for schools in similar neighborhoods.
There was a large "clustering" of the outcomes in schools indicated by the intraclass correlation coefficients (ICCs), especially snack food including sweetened beverages and processed packaged snacks, and fast food outcomes. Food availability near schools and/or wellness policies within schools might contribute to this "clustering."
The results of this study can be used to determine the sample size to detect intervention effects in future obesity prevention and behavioral-change studies in NYC schools and other similar populations. The study concludes that larger sample sizes than previously thought might be needed.