The GRoceries Aimed at Increasing Nutrition Study
GRAINS
Prompting a Switch From Refined Grains to Whole Grains in an Online Grocery Store Using Marketing Nudges and Financial Incentives
2 other identifiers
interventional
216
1 country
1
Brief Summary
Only 2% of Americans meet the recommended levels of whole grain consumption, despite its association with reduced risk of type 2 diabetes. This study aims to assess if consumers with prediabetes or type 2 diabetes can be encouraged to switch from buying refined grain products to whole grain products when shopping for groceries online. The study will use personalized marketing strategies, with or without discounts which adjust based on purchasing behavior, to promote whole grain consumption.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P75+ for not_applicable type-2-diabetes
Started Oct 2025
1 active site
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
Click on a node to explore related trials.
Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
July 25, 2025
CompletedFirst Posted
Study publicly available on registry
September 11, 2025
CompletedStudy Start
First participant enrolled
October 14, 2025
CompletedPrimary Completion
Last participant's last visit for primary outcome
February 16, 2027
ExpectedStudy Completion
Last participant's last visit for all outcomes
February 16, 2027
May 19, 2026
May 1, 2026
1.3 years
July 25, 2025
May 15, 2026
Conditions
Keywords
Outcome Measures
Primary Outcomes (1)
Change in calories purchased from products that are majority whole grains over time
The study team will use random-effects linear regression models to compare within-subject changes in the calories purchased from whole grains, adjusting for repeated measures, to examine trends over time.
18 weeks
Secondary Outcomes (16)
Change in calories purchased from products that are majority refined grains over time
18 weeks
Percent of cart spent on whole grains (total dollar on whole grains/cart total)
18 weeks
Change in dollars spent on products that are majority whole grains over time
18 weeks
Assessing whole and refined grain purchasing frequency
Assessed at baseline and in end-of-study survey (Week 18)
Percentage of time grains were purchased as whole and refined grains
Assessed at baseline and in end-of-study survey (Week 18)
- +11 more secondary outcomes
Study Arms (3)
Control
NO INTERVENTIONCompletion of weekly grocery shopping in a version of the study store without any interventions (i.e., without marketing nudges and financial incentives)
Marketing Nudges Only
EXPERIMENTALMarketing nudges encouraging whole grain purchasing, including displaying whole grains (e.g., whole wheat bread, brown rice) at the top of the study's online grocery store, featuring whole grain banner displays, and offering product swaps to highlight whole grain alternatives
Marketing Nudges + Dynamically Adapted Financial Incentives
EXPERIMENTALMarketing nudges encouraging whole grain purchasing, including displaying whole grains (e.g., whole wheat bread, brown rice) at the top of the study's online grocery store, featuring whole grain banner displays, and offering product swaps to highlight whole grain alternatives, plus personalized financial incentives with individual incentive amounts optimized weekly based on prior whole grain purchasing behavior and engagement
Interventions
Marketing nudges encouraging whole grain purchasing, including displaying whole grains (e.g., whole wheat bread, brown rice) at the top of the study's online grocery store, featuring whole grain banner displays, and offering product swaps to highlight whole grain alternatives
Marketing nudges encouraging whole grain purchasing, including displaying whole grains (e.g., whole wheat bread, brown rice) at the top of the study's online grocery store, featuring whole grain banner displays, and offering product swaps to highlight whole grain alternatives, plus personalized financial incentives with individual incentive amounts optimized weekly based on prior whole grain purchasing behavior and engagement
Eligibility Criteria
You may qualify if:
- Age 45 - 70 years.
- Able to provide consent.
- Resident of Philadelphia, Bucks, Delaware, Chester, or Montgomery Counties in Pennsylvania.
- Consume \<5 servings of whole grains per week.
- Use online grocery shopping at least once per month.
- Have access to a credit or debit card to pay for groceries purchased.
- Have reliable internet access.
- Speak English.
- Penn Medicine patient diagnosed with prediabetes or diabetes (identified using ICD-10 codes R73.03, E11).
You may not qualify if:
- Not able to speak English.
- Not able to provide consent.
Contact the study team to confirm eligibility.
Sponsors & Collaborators
- University of Pennsylvanialead
- National Institute on Aging (NIA)collaborator
- American Heart Associationcollaborator
Study Sites (1)
University of Pennsylvania
Philadelphia, Pennsylvania, 19104, United States
MeSH Terms
Conditions
Condition Hierarchy (Ancestors)
Study Officials
- PRINCIPAL INVESTIGATOR
Sophia V Hua, PhD, MPH
Department of Medical Ethics and Health Policy, Perelman School of Medicine
Central Study Contacts
Study Design
- Study Type
- interventional
- Phase
- not applicable
- Allocation
- RANDOMIZED
- Masking
- NONE
- Masking Details
- Participants will be informed that they will be randomly assigned to one of the three intervention arms, but they will not be told which group they are in. It will be necessary to omit these details so that participants will shop for their groceries as they would do in the real-world. The study team hopes this approach minimizes the chances that the participant will purchase foods that they think the study team wants them to purchase. Participants will be fully informed about the randomization process. To conceal the study's purpose, participants will be told that the study team is conducting consumer market research about online shopping experiences but will not be told the study team is specifically interested in understanding the effects of marketing and incentives on whole grain purchases. Participants will be fully debriefed at the end of the study.
- Purpose
- PREVENTION
- Intervention Model
- PARALLEL
- Sponsor Type
- OTHER
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
July 25, 2025
First Posted
September 11, 2025
Study Start
October 14, 2025
Primary Completion (Estimated)
February 16, 2027
Study Completion (Estimated)
February 16, 2027
Last Updated
May 19, 2026
Record last verified: 2026-05
Data Sharing
- IPD Sharing
- Will share
- Time Frame
- One year after publication of the main trial results.
- Access Criteria
- The PI will review any and all requests to access the de-identified study data.
All data will be de-identified. De-identified IPD that underlie results in a publication can be requested by other researchers. The PI will review any and all requests to access the de-identified study data. SecureShare or PennBox, both secure methods to transfer files, will be used to transfer data.