NCT06263621

Changing Portion Size Descriptions in a Cafeteria

Changing Restaurant Portion Size Descriptions to Encourage Selection and Intake of Smaller Meals: a Field Experiment

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 101,481 (actual)
• Sponsor: University of Pennsylvania · Academic / Other
• Sex: All
• Age: —
• Healthy volunteers: Accepted

Summary

The goal of this this intervention is to test the degree to which a portion size labeling intervention influences consumer selection of smaller portions at two large cafés. The main question it aims to answer is: Do consumers order fewer calories when the portion size label for the smaller entree is called "standard" instead of "small"? Participants will order lunch as usual in the two cafes (one intervention, one control) for 5.5 months, and all order items will be recorded in the check-out system. One cafe will receive the labeling intervention, while the other will not. Researchers will compare the average calories per order between the two cafes to see if there are differences.

Detailed description

The investigators will work with two cafés that will start offering two size options for their entrées. The cafés will go through three phases: a baseline phase where there are two portion sizes and no intervention (6 weeks), an intervention phase where the portion size labeling strategy will be implemented (7 weeks), and then a final phase where the portion size intervention is removed (7 weeks). During the baseline period, the smaller-sized entrée will not receive a label, and the larger-sized entrée will be called "Large." During the intervention period for the control café, labeling will stay the same, but in the intervention café, the smaller size will be labeled "Standard" and the larger size will be called "Large." In the post-intervention period, the smaller-sized entrée in the intervention café will have no label so that it resembles the control café.

Conditions

• Food Selection
• Obesity
• Weight Gain
• Food Preferences

Interventions

Type	Name	Description
BEHAVIORAL	Intervention "Standard"	The two cafes will offer entrees in two sizes, a smaller and larger size. In the intervention cafe, the smaller size will be labeled "Standard" during the intervention period, and "Small" during all other times. In the control cafe, the smaller size will always be labeled "Small." The larger size will always be labeled "Large" for both cafes during the duration of the study.

Timeline

• Start date: 2024-01-11
• Primary completion: 2024-05-29
• Completion: 2024-05-29
• First posted: 2024-02-16
• Last updated: 2024-07-11

Locations

2 sites across 1 country: United States