Intervening to Influence Fast-Food Choices: Assessing Response Generalization in Nutrition-Related Behavior

A large-scale intervention, designed to increase healthier fast-food consumption, was evaluated at a national fast-food chain. Participants included fast-food consumers at three separate restaurant locations in southwestern Virginia. Each restaurant received three phases, consisting of fourteen days each. Two of the restaurants were exposed to two conditions, A (Baseline) and B (Intervention), while the other restaurant served as a control. Restaurant 1 received the following phases, with each phase lasting two weeks: A--B--A. Restaurant 2 received A--A--B, and Restaurant 3 received A--A--A. Research assistants distributed discount coupons on a new healthy sandwich to consumers during Condition B in Restaurants 2 & 3. This sandwich was available in a healthy combo including salad and water, and a regular combo including soda and fries. At all 3 locations, research assistants collected receipts showing all total menu item sales every day during the six-week intervention. Analyses of variance revealed consumers purchased the healthy sandwich significantly more during the incentive conditions, and also purchased the regular combo more frequently than the healthier combo during the intervention condition. Implications for the social validity of using incentives to motivate nutrition-related behaviors are discussed.