Shop For Success: Experimental Grocery Store Study

Price Elasticity of Fruit (Shop For Success)

The purpose of this research is to study how the price of foods affects food buying choices at the grocery store. The researchers are interested in this topic because the price of foods can have a big impact on what people choose to buy and prices change over time. The researchers are doing this study to see how changes in food prices affect what foods mothers choose for their families.

Study Overview

• Status: Completed
• Conditions: Obesity; Overweight
• Intervention / Treatment: Other: Own-Price Elasticity; Other: Cross-Price Elasticity

Detailed Description

It is well known that the price of a given food affects the amount of that food an individual purchases. However, little is known about how specific groups, such as overweight/obese and those with lower incomes, change their food purchasing decisions depending on food price changes. Evidence has shown that these groups have lower quality diets and worse health outcomes than their normal weight and higher income counterparts. Therefore, it is important to gain a better understanding of how food price changes affect purchasing decisions among these populations in order to develop targeted nutrition interventions to improve their diet quality. To investigate this, the researchers will create a laboratory-based grocery store, in which pictures of foods will be used to substitute actual food. Food prices will be indicated on each picture. Participants will be given play money and a budget, and ask them to "purchase" foods in the mock grocery store. The price of food will be changed throughout the study to investigate how participants change their purchasing decisions based on these price changes.

• Study Type: Interventional
• Enrollment (Actual): 73
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • North Dakota
    • Grand Forks, North Dakota, United States, 58203
      • USDA Grand Forks Human Nutrition Research Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: Female

Description

Inclusion Criteria:

• Have at least one child up to 18 years of age residing in the household
• Primary grocery shopper for the household
• No health conditions or food practices that substantially limit food choice
• Not currently pregnant
• Consent to the study design

Exclusion Criteria:

• Male
• < 18 years of age
• Not a mother, or children not living with subject in their household
• No children below the age of 18 years of age
• Not the primary grocery shopper for their household
• Health conditions or food practices that substantially limit food choice
• Currently pregnant

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Factorial Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Own-Price Elasticity; The price of fruit will vary (own-price elasticity) while the price of all other foods in the "mock" grocery store will remain constant.	Other: Own-Price Elasticity; The price of fruit will be 75%, 100%, or 125% of the reference price, but the price of other foods will remain the same.
Experimental: Cross-Price Elasticity; The price of fruit will remain constant while the price of other foods in the "mock" grocery store will vary (cross-price elasticity).	Other: Cross-Price Elasticity; The price of fruit will remain the same, but the price of other foods will be 75%, 100%, or 125% of the reference price.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Price elasticity of fruit	Percent change in the amount of fruit purchased (gram weight) for every percent change in the price of a given food.	Baseline

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Nutrient density of purchased foods	Ratio of low nutrient-dense food purchases to high nutrient-dense food purchases	Baseline

Collaborators and Investigators

• Sponsor: USDA Grand Forks Human Nutrition Research Center

Study record dates

Study Major Dates

• Study Start (Actual): August 22, 2019
• Primary Completion (Actual): March 25, 2020
• Study Completion (Actual): March 25, 2020

Study Registration Dates

• First Submitted: September 18, 2019
• First Submitted That Met QC Criteria: September 18, 2019
• First Posted (Actual): September 20, 2019

Study Record Updates

• Last Update Posted (Actual): February 2, 2022
• Last Update Submitted That Met QC Criteria: January 18, 2022
• Last Verified: January 1, 2022

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Body Weight; Overweight
• Other Study ID Numbers: GFHNRC155

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No