How the Gus Schumacher Produce Prescription Program Works: An Adaptation of a Nutrition Incentive Theory of Change.

The United States Department of Agriculture's Gus Schumacher Nutrition Incentive Program (GusNIP) supports nutrition incentive (NI) and produce prescription programs (PPRs). PPRs allow healthcare providers to "prescribe" fruits and vegetables (FVs) to patients experiencing low income and/or chronic disease(s) and who screen positive for food insecurity. We developed a Theory of Change (TOC) that summarizes how and why PPRs work, identifies what the programs hope to achieve, and elucidates the causal pathways necessary to achieve their goals. We created the PPR TOC through an iterative, participatory process that adapted our previously developed GusNIP NI TOC. The participatory process involved food and nutrition security experts, healthcare providers, PPR implementors, and PPR evaluators reviewing the existing NI TOC and suggesting modifications to accurately reflect PPRs. The resulting TOC describes the mechanisms, assumptions, rationale, and underpinnings that lead to successful and equitable outcomes. Modifications of the NI TOC centered around equity and focused on inclusion of healthcare as an additional partner and the importance of health and healthcare utilization as outcomes. The TOC describes how the GusNIP PPR program reaches its goals. This understanding will be useful for PPR developers, implementers, funders, and evaluators for describing the pathways, assumptions, and foundations of successful PPRs.