Comparison of front-of-package nutrition labelling schemes in Costa Rica: a multi-arm parallel-group randomised controlled trial assessing objective understanding and purchase intention.

Different front-of-package labelling (FOPL) schemes have been developed worldwide to encourage informed and healthier food purchase decisions. However, few studies have formally compared different schemes, particularly in the Latin American context. This study aimed to assess the effects of four different FOPL schemes on the objective understanding of the nutritional content and intention to purchase products.