Diet Improvement Through Normative Experimentation

"Participants are shown a version of NUSMart which includes Nutri-Score labels that are enabled and displayed besides all the products in the store. Additionally, they are shown a video that gives them background information about Nutri-Score labels and describes the following features enabled in this intervention:~* Norm-based messaging will be displayed in the form of a happy or sad emoticon based on whether the participant's current basket average Nutri-Score (weighted by number of servings) is above or below other shoppers (Nutri-Score=3.98).~* Peer comparison will be implemented as a vertical ruler display of the participant's current basket average Nutri-Score (weighted by number of servings) as well as that of their peers.~Nutri-Score=3.98 was chosen as it is 10% better than the mean Nutri-Score of baskets purchased by participants in the Nutri-Score labelled intervention arm of a prior study."

"Participants are informed that they have received an additional $5 towards their participant reimbursement. However, this amount will be forfeited if they check-out with a basket average Nutri-Score (weighted by the number of servings) that falls below the average Nutri-Score of other shoppers i.e. 3.98. An indicator on the screen that informs the participants of this potential forfeiting will be included."