Objective: Sample size and statistical power calculation should consider clustering effects when schools are the unit of randomization in intervention studies. The objective of the current study was to investigate how student outcomes are clustered within schools in an obesity prevention trial. Method: Baseline data from the Food, Health &…

This study investigates the link between process evaluation components and the outcomes of a school-based nutrition curriculum intervention, "Choice, Control and Change". Ten New York City public middle schools were recruited and randomly assigned into intervention or control condition. The curriculum was to improve sixth to seventh…