Impact of schoolchildren's involvement in the design process on the effectiveness of healthy food promotion materials☆

Marketing techniques may improve children's vegetable consumption. However, student participation in the design of marketing materials may increase the material's salience, while also improving children's commitment and attitudes towards healthy eating. The impact of student-led design of vegetable promotional materials on choice and consumption was investigated using 1614 observations of students' vegetable choice and plate waste in four public elementary schools in Kearney, Nebraska. Data were collected on children's vegetable choice and consumption in four comparison groups: 1) control; 2) students designed materials only; 3) students were exposed to promotional materials only; and 4) students designed materials that were then posted in the lunchroom. Vegetable choice and consumption data were collected through a validated digital photography-based plate-waste method. Multivariate linear regression was used to estimate average treatment effects of the conditions at various time periods. Dependent variables were vegetable choice and consumption, and independent variables included the condition, time period, and interaction terms, as well as controls for gender and grade. Relative to baseline, students in group 4 doubled their vegetable consumption (p < 0.001) when materials were posted. Vegetable consumption remained elevated at a follow-up 2-3 months later (p < 0.05). Students in group 3 initially increased the quantity of vegetables selected (p < 0.05), but did not increase consumption. In the follow-up period, however, students in group 3 increased their vegetable consumption (p < 0.01). Involving elementary-aged students in the design of vegetable promotional materials that were posted in the lunchroom increased the amount of vegetables students consumed.