Economic analysis of three interventions of different intensity in improving school implementation of a government healthy canteen policy in Australia: costs, incremental and relative cost effectiveness

Background: No evaluations of the cost or cost effectiveness of interventions to increase school implementation of food availability policies have been reported. Government and non-government agency decisions regarding the extent of investment required to enhance school implementation of such policies are unsupported by such evidence. This study sought to i) Determine cost and cost-effectiveness of three interventions in improving school implementation of an Australian government healthy canteen policy and; ii) Determine the relative cost-effectiveness of the interventions in improving school implementation of such a policy. Methods: An analysis of the cost and cost-effectiveness of three implementation interventions of varying support intensity, relative to usual implementation support conducted during 2013-2015 was undertaken. Secondly, an indirect comparison of the trials was undertaken to determine the most cost-effective of the three strategies. The economic analysis was based on the cost of delivering the interventions by health service delivery staff to increase the proportion of schools 'adherent' with the policy. Results: The total costs per school were $166,971, $70,926 and $75,682 for the high, medium and low intensity interventions respectively. Compared to usual support, the cost effectiveness ratios for each of the three interventions were: A$2982 (high intensity), A$2627 (medium intensity) and A$4730 (low intensity) per percent increase in proportion of schools reporting 'adherence'). Indirect comparison between the 'high' and 'medium intensity' interventions showed no statistically significant difference in cost-effectiveness. Conclusions: The results indicate that while the cost profiles of the interventions varied substantially, the cost-effectiveness did not. This result is valuable to policy makers seeking cost-effective solutions that can be delivered within budget.