Multi-strategic intervention to enhance implementation of healthy canteen policy: a randomised controlled trial

BACKGROUND Internationally, governments have implemented school-based nutrition policies to restrict the availability of unhealthy foods from sale. The aim of the trial was to assess the effectiveness of a multi-strategic intervention to increase implementation of a state-wide healthy canteen policy. The impact of the intervention on the energy, total fat, and sodium of children's canteen purchases and on schools' canteen revenue was also assessed. METHODS Australian primary schools with a canteen were randomised to receive a 12-14-month, multi-strategic intervention or to a no intervention control group. The intervention sought to increase implementation of a state-wide healthy canteen policy which required schools to remove unhealthy items (classified as 'red' or 'banned') from regular sale and encouraged schools to 'fill the menu' with healthy items (classified as 'green'). The intervention strategies included allocation of a support officer to assist with policy implementation, engagement of school principals and parent committees, consensus processes with canteen managers, training, provision of tools and resources, academic detailing, performance feedback, recognition and marketing initiatives. Data were collected at baseline (April to September, 2013) and at completion of the implementation period (November, 2014 to April, 2015). RESULTS Seventy schools participated in the trial. Relative to control, at follow-up, intervention schools were significantly more likely to have menus without 'red' or 'banned' items (RR = 21.11; 95% CI 3.30 to 147.28; p ≤ 0.01) and to have at least 50% of menu items classified as 'green' (RR = 3.06; 95% CI 1.64 to 5.68; p ≤ 0.01). At follow-up, student purchases from intervention school canteens were significantly lower in total fat (difference = -1.51 g; 95% CI -2.84 to -0.18; p = 0.028) compared to controls, but not in energy (difference = -132.32 kJ; 95% CI -280.99 to 16.34; p = 0.080) or sodium (difference = -46.81 mg; 95% CI -96.97 to 3.35; p = 0.067). Canteen revenue did not differ significantly between groups. CONCLUSION Poor implementation of evidence-based school nutrition policies is a problem experienced by governments internationally, and one with significant implications for public health. The study makes an important contribution to the limited experimental evidence regarding strategies to improve implementation of school nutrition policies and suggests that, with multi-strategic support, implementation of healthy canteen policies can be achieved in most schools. TRIAL REGISTRATION Australian New Zealand Clinical Trials Registry ( ACTRN12613000311752 ).