Understanding multi-level policy implementation in the national school lunch and breakfast programs: a mixed-methods and agent-based modeling protocol.

backgroundThe Healthy, Hunger-Free Kids Act (2010) improved the nutritional quality of school meals in the U.S. by aligning the National School Lunch and Breakfast Programs with updated dietary guidelines. However, 2018 federal flexibilities in sodium, whole grains, and milk standards shifted key implementation decisions to local school districts. This created variability in uptake and potential inequities in diet quality and health outcomes, particularly among students from low-resource settings. Key drivers of differential uptake, and decision-making by local districts, is not well understood.

methodsIn this three-phase study, we will use a mixed-method approach to examine the implementation of sodium, whole grains, and milk flexibilities across the many levels involved in implementing the National School Lunch and School Breakfast Programs and describe the impact of flexibility implementation on child health-related outcomes. In phase 1, we will conduct a nationally representative survey of school district food service directors to assess current flexibility implementation practices and determinants of decision-making. We will combine these primary data with publicly available state level and school district data to understand how decisions relate to school meal participation and health-related outcomes. Phase 2 involves interviewing school food industry actors to understand how National School Lunch and School Breakfast Programs policy changes influence decisions that change food supply and distribution. In phase 3, we leverage insights from the actors surveyed and interviewed in phases 1 and 2 to develop an agent-based model. We will use this model to analyze potential effects of different policy changes on child health, examination of ways to improve effective and equitable district-level implementation of the National School Lunch and School Breakfast Program, and to develop tools to inform real-world policymaking. DISCUSSION: This study offers critical insights into the complexity of school food systems, emphasizing the role of decision making by actors involved in National School Lunch and School Breakfast Program implementation. Results will inform evidence-based strategies to support equitable implementation of school nutrition policies, expand policy implementation science by providing insight into the mechanisms that shape variation in implementation and health-related outcomes, and contribute methodological innovation using an agent-based model as a virtual policy laboratory.