Effects of More Prominent Shelf Placement of Healthier Food Products on Supermarket Purchases: A Co-Designed Pilot Study ^†

Supermarkets are the primary source of food for many New Zealanders. This retail food environment is therefore an important setting for action to improve unhealthy diets. There is growing evidence that shopper purchases can be influenced by in-store interventions, such as signage and price discounts on healthier foods. Despite this, research interventions fail to be implemented by retailers in real world settings because they are not cost-effectiveness. A retailer-academic collaboration aimed to co-design and pilot commercially sustainable strategies to increase sales of healthier foods relative to less healthy foods in a major supermarket chain. Two co-design workshops were held, led by an experienced facilitator and involving supermarket corporate strategy team members (nutrition/health, purchasing, category management, and communications) and public health nutrition academics, to identify potential interventions. These were mapped against choice architecture evidence frameworks and retailer strategic priorities and one intervention, more prominent shelf placement of healthier products, was selected for a pilot study. A 12-week controlled trial was undertaken in six Auckland supermarkets (three intervention and three matched control stores) April–July 2019. Products in one selected category were ranked by healthiness (nutrient levels and nutrient profile), and their shelf placement was altered in intervention stores so that healthier products were placed at eye level and less healthy products were placed on lower shelves. No changes were made to shelf layout in the control stores. Weekly audits were conducted to check compliance with intervention and control store planograms (product placement). The primary outcome of interest is change in sales of healthier products relative to total category sales. Sales relative to pre-intervention and post-intervention periods will also be evaluated. Secondary outcomes include overall nutrient profile of category products sold, shopper purchases, shopper perceptions, and retailer feedback. The study will be complete in October 2019 and initial results will be presented.