Cluster randomized controlled trial of a consumer behavior intervention to improve healthy food purchases from online canteens

Background: School canteens represent an opportune setting in which to deliver public health nutrition strategies because of their wide reach and frequent use by children. Online school-canteen ordering systems, where students order and pay for their lunch online, provide an avenue to improve healthy canteen purchases through the application of consumer-behavior strategies that have an impact on purchasing decisions. Objective: We assessed the efficacy of a consumer-behavior intervention implemented in an online school-canteen ordering system in reducing the energy, saturated fat, sugar, and sodium contents of primary student lunch orders. Design: A cluster-randomized controlled trial was conducted that involved 2714 students (aged 5-12 y) from 10 primary schools in New South Wales, Australia, who were currently using an online canteen ordering system. Schools were randomized in a 1:1 ratio to receive either the intervention (enhanced system) or the control (standard online ordering only). The intervention included consumer-behavior strategies that were integrated into the online ordering system (targeting menu labeling, healthy food availability, placement, and prompting). Results: Mean energy (difference: -567.25 kJ; 95% CI: -697.95, -436.55 kJ; P < 0.001), saturated fat (difference: -2.37 g; 95% CI: -3.08, -1.67 g; P < 0.001), and sodium (difference: -227.56 mg; 95% CI: -334.93, -120.19 mg; P < 0.001) contents per student lunch order were significantly lower in the intervention group than in the control group at follow-up. No significant differences were observed for sugar (difference: 1.16 g; 95% CI: -0.50, 2.83 g; P = 0.17). Conclusions: The study provides strong evidence supporting the effectiveness of a consumer-behavior intervention using an existing online canteen infrastructure to improve purchasing behavior from primary school canteens. Such an intervention may represent an appealing policy option as part of a broader government strategy to improve child public health nutrition.