To build on prior laboratory studies related to injunctive food norms, the goal of this field-experiment was to explore factors that influence patrons' food choices in a university cafeteria.
To evaluate the influence of food messaging (ie, injunctive norms) at a designated food station in the cafeteria, with the goal of encouraging healthier food choices and exploring factors that influence patrons’ food choices.
Study Design, Setting, Participants
We employed an interrupted time series, quasi-experimental design. During the 10-day baseline phase, patrons were asked to complete a survey. During the intervention, 3 copies of healthy injunctive signs were placed in the cafeteria and patrons were asked about the signage.
Within each survey, we collected the patrons’ food choices, noting how many and what type of side items each purchased to compare the proportion of patrons purchasing at least 1 healthy side item using a 2-sample proportion test. During the intervention, we asked patrons if they saw the sign and what they remembered. Several items from a modified version of The Eating Motivation Survey was also asked to determine what influenced patrons’ food choices.
The 2-sample proportion test for 200 baseline participants and 170 intervention participants (z = −1.55, P = .12) did not indicate a difference in the proportion of patrons purchasing at least 1 healthy side-item during the experimental weeks. Approximately 40% of the patrons during intervention week remembered seeing the signage and 24% recalled some detail of the signage.
This study sought to determine if employing social norms through food signage influenced patron's side-item choice. While the results did not show a significant difference in choosing healthier items, the patrons' recall of the sign shows promise for how colleges can implement and encourage healthier eating habits on their campuses.
Appendix. Supplementary data
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