CONSORT: Health inequalities in the food system

National strategies tackling dietary health inequalities include Healthy Start vouchers and free school meals, reducing the costs of healthier food to the lowest income families. Local authorities can also act via the planning, business rates, education and other systems and a number of organisations support local authorities to develop food strategies. Our aim is to provide some of the first applied experimental evidence on the impacts of group model building on policy implementation, particularly for dietary health inequalities. In this application, we will conduct pilot work to refine the intervention followed by a randomised controlled feasibility trial of a group model building intervention compared to ‘usual care’ (i.e. no intervention), in the 40% most deprived local authorities in England (n=30 in each group). This will estimate potential effect sizes on the number of policies planned or implemented with the potential to impact on dietary health inequalities, and the potential of these interventions to achieve system change. A process evaluation will use observations and survey data to explore how participants understanding of the problem and potential solutions evolve during the intervention workshop. Intervention costs will be documented. We will collect and curate local data on dietary health inequalities to inform group model building and gain greater understanding of local variations in the causes of dietary health inequalities.