Process evaluation results from the HEALTHY nutrition intervention to modify the total school food environment.

The process evaluation of HEALTHY, a large multi-center trial to decrease type 2 diabetes mellitus in middle school children, monitored the implementation of the intervention to ascertain the extent that components were delivered and received as intended. The purpose of this article is to report the process evaluation findings concerning the extent to which the HEALTHY nutrition intervention was implemented during the HEALTHY trial. Overall, the observed fidelity of implementing nutrition strategies improved from baseline to the end of the study. By the last semester, all but two nutrition process evaluation goals were met. The most challenging goal to implement was serving high fiber foods, including grain-based foods and legumes. The easiest goals to implement were lowering the fat content of foods offered and offering healthier beverages. The most challenging barriers experienced by research dietitians and food service staff were costs, availability of foods and student acceptance. Forming strong relationships between the research dietitians and food service staff was identified as a key strategy to meet HEALTHY nutrition goals.