Data collection
Field work was performed between 15th of May and 13th of June 2012, in order to obtain a large variety of menus containing mixed and non-mixed dishes, and fish and meat dishes, from a 3-month menu cycle. The same menu was evaluated at least once, at two different schools. Each child and each school were evaluated once during this period.
Aggregated nonselective plate waste of main dish was collected for each child using two different methods: weighing and visual estimation.