7.3.6. School-based programmes

This intervention further scales-up and strengthens policies currently in place in many OECD countries mandating the inclusion of physical activity classes in the school curricula. More specifically, this intervention entails the inclusion of classroom lessons on the benefits of physical activity led by trained teachers and of moderate-to-vigorous physical activity sessions (including playing sports and aerobic exercise) as part of the school curriculum. In addition, the intervention also entails the distribution of nutritional education materials and the provision of healthful foods in school canteens.

A meta-analysis of school-based programmes promoting both a healthier diet and additional physical activity found that these interventions lead to an overall mean reduction in BMI of 0.30 kg/m2 [Wang et al., 2015 [63]]. This analysis already takes into account students’ compliance, so the average reduction is equally applied to all the schoolchildren. For each affected child, there is a linear reduction in BMI within a year of the programme’s implementation until the individual’s BMI drops by 0.30 kg/m2, after which it stays constant on the lower parallel trajectory until the child graduates from school at age 18. It is also assumed that such programmes have a long-term effect as children are expected to acquire a habit of doing physical activity or eating more healthily. Specifically, consistent with the previous OECD analysis [Sassi, Cecchini, Lauer and Chisholm, 2009 [53]], it is assumed that after children turn 18, there is a linear decrease of the programme’s effectiveness by 50% (i.e. BMI is reduced by 0.15 kg/m2) over one year parallel to their baseline BMI trajectory, and then it stays at this level for the rest of life.

Since any policy in public schools is likely to be mandatory and apply to almost all students (probably with some exceptions for health-related reasons), it is assumed that about 90% of all public school students in both primary and secondary education can be affected (ages 8-18). If not selected in the first year in which the intervention is implemented, students remain ineligible for participation for the rest of their life.

The cost of the programme includes the programme component and the cost of delivering the intervention in the schools. Half of the total cost is spent on programme organisation costs, while the remaining half is split between training of teachers and food service staff, extra teaching and additional curricular activities, e.g. guest speakers, brochures, books, posters and equipment. The single most expensive item is extra teaching hours. Costs do not include changes in food service contracts, vouchers/coupons from sponsors and school nurse time. The annual cost is estimated to vary between USD PPP 2.78 and USD PPP 3.14 per capita across the countries included in the analysis.