Abstract:
Background: Unhealthy food environments foster unhealthy diets through widespread availability of cheap, highly palatable, heavily promoted, energy dense and nutrient-poor foods. Government policies and actions are essential to increase the healthiness of food environments and reduce obesity and diet-related NCDs. The INFORMAS group has developed a Healthy Food Environment Index (Food-EPI) to monitor and benchmark government policies and actions on food environments. However, the relative contribution of each policy approach to improving population nutrition has not been established. It is thus important to establish these relative contributions, in order to quantify and numerically assess the implementation of governments’ food policies to improve population nutrition. Aim: The overall aim of this study was to develop a weighting system for the 19 good practice statements and 7 policy domains within the Food-EPI, based on international evidence and expert opinions in order to develop a summary score from ratings of the Food-EPI 19 statements. Methods: A modified Delphi technique was developed which incorporated the Analytic Hierarchy Process method, whereby the policy domains and their respective good practice statements were rated using pairwise comparisons within Excel spreadsheets. The 27 international food/nutrition policy experts who participated in the Delphi process were provided with a 48 page summary of recent evidence on the influence of each good practice statement on population nutrition to supplement their own expertise. Results: Policies such as taxing unhealthy foods (0.241), restricting media promotion (0.220), school food provision (0.217) and minimising taxes on healthy foods (0.213), were given the highest weights. Policies that received the lowest weights were menu board labelling (0.096), approving and reviewing nutrition and health claims (0.079), workplace policies in the private sector (0.063). Overall food domains that received the highest weights were the Food Price (0.194) and Promotion (0.182) domains, with Food Trade domain receiving the lowest weight (0.109). However, ratings given by experts for several policies such as those within the Trade, Retail, Promotion and Labelling domain lacked consensus. Conclusion: This study represents the first known attempt at using the Delphi methodology and Analytic Hierarchy Process to derive weights on the relative importance of implementing recommended good practice food policies to improving population nutrition. Prioritising good practice policy areas such as taxing unhealthy foods, restricting media promotion towards children is important to focus public health efforts to the most effective strategies to improve population nutrition. Future rounds of the Delphi is needed to clarify policy weights with lower consensus and add in further weights for other policy considerations (e.g. effects on equity and supporting child and consumer rights).