Clinical trial NCT02359916: Delays to Influence Snack Choice
Official title: Time Over Money? A Novel System to Influence Snack Machine Choices
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Food Choice
Lead sponsor: Rush University Medical Center
Sponsor class: OTHER
First posted: 2015-02-10
Enrollment: 32662
Sex: ALL
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Observational model: ECOLOGIC_OR_COMMUNITY
Time perspective: CROSS_SECTIONAL
Sampling method: NON_PROBABILITY_SAMPLE
Study population: This is an environmental intervention. No subjects will be recruited or enrolled.

Brief summary: The pervasiveness of high-calorie, nutrient-poor snacks in the environment is believed to have contributed to the epidemic levels of obesity and cardiometabolic disease in the U.S. This project tests whether a novel snack vending machine system that uses brief time delays to reduce the immediacy of reward from unhealthy snacks will improve the healthfulness of snack choices. If successful, this project will identify a new environmental intervention that could contribute substantially to obesity and cardiometabolic disease prevention efforts in schools, worksites, and other settings.

Detailed description: Environmental interventions that address the high availability of unhealthy snacks in the environment are needed to prevent a large projected increase in the incidence of obesity and cardiometabolic disease in the U.S. Prior studies from the investigators group and others suggests that the human preference for immediate gratification from food drives dietary overconsumption, but this knowledge has not yet translated to more effective dietary intervention strategies. This project tests whether a novel snack vending machine system that uses brief time delays to reduce the immediacy of reward from unhealthy snacks will improve the healthfulness of snack choices. This study uses an experimental design to compare brief time delays, two forms of 25% differential pricing, and time delays combined with both forms of 25% differential pricing on their ability to increase purchasing of healthy snacks. Test machines will be placed in existing, high-volume vending locations, and each of these five experimental conditions will run for roughly four weeks. Additionally, baseline purchasing under no intervention will be monitored for four weeks before and four weeks after the five experimental conditions. Specific Aim 2 compares the effects of these five interventions against baseline on the proportion of total vending sales from healthy snacks. Specific Aim 3 tests whether time delays or differential pricing harm overall vending machine sales in the test machines. This study not only tests a compelling theory about the effects of time delays and immediate reward on food choice, but evaluates the efficacy and feasibility of a novel intervention to improve the healthfulness of snack choices in worksites, schools, and other settings.

Eligibility criteria: Inclusion Criteria:

* Not applicable

Exclusion Criteria:

* Not applicable

Primary outcomes:
measure: Proportion of Healthy Snacks Purchased
timeFrame: 28 weeks per vending location
Secondary outcomes:
measure: Total Daily Vending Revenue in US$/Day
timeFrame: Number of days per condition were as follows - Baseline: 119 days, Discount only: 59 days, Delay only: 68 days, Delay + Discount: 49 days, Tax only: 73 days, Delay + Tax: 60 days
Other outcomes:
Locations:
city: Chicago
country: United States
facility: Rush University Medical Center
state: Illinois
Study officials:
affiliation: Associate Professor
name: Bradley M Appelhans, PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Appelhans BM, French SA, Olinger T, Bogucki M, Janssen I, Avery-Mamer EF, Powell LM. Leveraging delay discounting for health: Can time delays influence food choice? Appetite. 2018 Jul 1;126:16-25. doi: 10.1016/j.appet.2018.03.010. Epub 2018 Mar 15.