Impact of Environmental Nudges on Dietary Quality

Study Overview
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Brief Summary
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Purpose: The overall purpose of this study is to evaluate the impact of a suite of environmentally focused nudges on the nutritional quality of consumers' food selections. Participants:  2,000 US adults ages 18-25, at least 25% currently enrolled full-time in college, recruited from CloudResearch Prime Panels. Procedures: Participants will be randomly assigned to view food products with or without environmental nudges (eco-labels, peer comparison message, and swaps). They will be asked to select items that they most wish to purchase and will then be asked a series of questions about the products and nudges. Questions will also include standard socio-demographic variables.

Detailed Description
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Participants will be recruited from CloudResearch Prime Panels (an online panel research company). Study participants include 2,000 young adults between 18 and 25 years old with at least 25% currently enrolled in college, recruited to match census distribution of race/ethnicity and gender. Participants will electronically acknowledge their consent to participate in the study. On the study platform (Qualtrics), participants will be randomly assigned to 1 of 2 arms with equal probability. Participants will complete a shopping task via an online 9-minute survey. They will view products displayed as if they were offered from a grocery store. Products will be frozen meals, such as burritos and pizza, snack items such as dried fruit and chips, and protein items, such as ground beef and chicken breasts. They will then be instructed to select 1 item they most wish to purchase from each category. Participants in the experimental arm will shop and receive environmental nudges in the form of labels, feedback, peer comparisons, and suggested product swaps. In the control arm, participants will conduct online shopping tasks without any environmental nudges. After selecting products, participants will answer questions about the products and labels, as well as standard socio-demographic questions.

Official Title
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Impact of Environmental Nudges on Dietary Quality

Conditions
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Healthy Diet

Intervention / Treatment
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* Behavioral: Environmental nudges


Participation Criteria
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Eligibility Criteria
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Inclusion criteria: 18 to 25 years old Currently resides in the United States Exclusion criteria: Completion of the survey in <1/3 of the median completion time

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 25 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Control<br>Participants will conduct online shopping tasks without any environmental nudges. This includes no labels, peer comparison messages, or suggested product swaps. | |
| Experimental: Environmental<br>Participants in the experimental arm will shop and receive environmental nudges in the form of labels, peer comparisons messages, and suggested product swaps. | Behavioral: Environmental nudges<br>* Participants will view protein, frozen meal, and snack products with eco-labels applied. For each category, they will then be instructed to select 1 item from that category they wish most to purchase. Categories will be shown in random order. If a participant selects a product with a red eco-label, they will be shown a peer comparison message and will be given an opportunity to switch to a product with a yellow or green eco-label.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Nutri-Score Scores | Healthfulness of product selections (operationalized as products' Nutri-Score scores). Products' Nutri-Score scores are calculated using the updated 2022 algorithm released by the Scientific Committee of the Nutri-Score (ScC). Scores range from -15 (Nutri-Score of A) to 40 (Nutri-Score of E), with lower scores indicating a more healthful product selection. | Immediately after exposure to intervention and product selection task, assessed during 1-time online study visit | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Carbon Footprint | Carbon footprint of product selections [operationalized as products' greenhouse gas emissions (GHGE) per 100g]. | Immediately after exposure to intervention and product selection task, assessed during 1-time online study visit | 
| Acceptability of Eco-Label Intervention | Acceptability of eco-labels on products, measured by an item adapted from Vargas-Meza et al., 2019. Likert responses are on a 1 to 5 scale, from Not at all (coded as 1) to A great deal (coded as 5), with higher scores representing a higher acceptability of eco-labels. | Immediately after exposure to intervention and product selection task, assessed during 1-time online study visit | 
| Acceptability of Swaps Intervention | Acceptability of environmental swaps, measured by an item adapted from Vargas-Meza et al., 2019. Likert responses are on a 1 to 5 scale, from Not at all (coded as 1) to A great deal (coded as 5), with higher scores representing a higher acceptability of swaps. | Immediately after exposure to intervention and product selection task, assessed during 1-time online study visit | 
| Acceptability of Peer Comparison Message Intervention | Acceptability of peer comparison messages, measured by an item adapted from Vargas-Meza et al., 2019. Likert responses are on a 1 to 5 scale, from Not at all (coded as 1) to A great deal (coded as 5), with higher scores representing a higher acceptability of peer comparison messages. | Immediately after exposure to intervention and product selection task, assessed during 1-time online study visit | 
| Health Elaboration | How much the participant reports thinking about the healthfulness of products when making selections. Likert responses are on a 1 to 5 scale, from Not at all (coded as 1) to A great deal (coded as 5), with higher scores representing a higher amount of thinking about the healthfulness of products. | Immediately after exposure to intervention and product selection task, assessed during 1-time online study visit | 
| Taste Elaboration | How much the participant reports thinking about the taste of products when making selections. Likert responses are on a 1 to 5 scale, from Not at all (coded as 1) to A great deal (coded as 5), with higher scores representing a higher amount of thinking about the taste of products. | Immediately after exposure to intervention and product selection task, assessed during 1-time online study visit | 
| Cost Elaboration | How much the participant reports thinking about the cost of products when making selections. Likert responses are on a 1 to 5 scale, from Not at all (coded as 1) to A great deal (coded as 5), with higher scores representing a higher amount of thinking about the cost of products. | Immediately after exposure to intervention and product selection task, assessed during 1-time online study visit | 
| Environmental Sustainability Elaboration | How much the participant reports thinking about the environmental sustainability of products when making selections. Likert responses are on a 1 to 5 scale, from Not at all (coded as 1) to A great deal (coded as 5), with higher scores representing a higher amount of thinking about the environmental sustainability of products. | Immediately after exposure to intervention and product selection task, assessed during 1-time online study visit | 
| Perceived Healthfulness of Sustainable Products | Participants' perceptions about the healthfulness of sustainable products. Likert responses are on a 1 to 5 scale, from Not at all (coded as 1) to Extremely (coded as 5), with higher scores representing a higher perceived healthfulness of sustainable products. | Immediately after exposure to intervention and product selection task, assessed during 1-time online study visit | 
| Perceived Healthfulness of Unsustainable Products | Participants' perceptions about the healthfulness of unsustainable products. Likert responses are on a 1 to 5 scale, from Not at all (coded as 1) to Extremely (coded as 5), with higher scores representing a higher perceived healthfulness of unsustainable products. | Immediately after exposure to intervention and product selection task, assessed during 1-time online study visit | 
| Perceived Sustainability of Sustainable Products | Participants' perceptions about the sustainability of sustainable products. Likert responses are on a 1 to 5 scale, from Not at all (coded as 1) to Extremely (coded as 5), with higher scores representing a higher perceived sustainability of sustainable products. | Immediately after exposure to intervention and product selection task, assessed during 1-time online study visit | 
| Perceived Sustainability of Unsustainable Products | Participants' perceptions about the sustainability of unsustainable products. Likert responses are on a 1 to 5 scale, from Not at all (coded as 1) to Extremely (coded as 5), with higher scores representing a higher perceived sustainability of unsustainable products. | Immediately after exposure to intervention and product selection task, assessed during 1-time online study visit | 
| Purchase Intentions of Sustainable Products | Participants' intentions to purchase a sustainable product in the next month. Likert responses are on a 1 to 5 scale, from Not at all likely (coded as 1) to Extremely likely (coded as 5), with higher scores representing a higher intention to purchase. | Immediately after exposure to intervention and product selection task, assessed during 1-time online study visit | 
| Purchase Intentions of Unsustainable Products | Participants' intentions to purchase an unsustainable product in the next month. Likert responses are on a 1 to 5 scale, from Not at all likely (coded as 1) to Extremely likely (coded as 5), with higher scores representing a higher intention to purchase. | Immediately after exposure to intervention and product selection task, assessed during 1-time online study visit | 
| Injunctive Norms | Participants' perceived approval from people important in their life for purchasing environmentally sustainable products. Likert responses are on a 1 to 5 scale, from Strongly disagree (coded as 1) to Strongly agree (coded as 5), with higher scores representing higher perceived approval about purchasing environmentally sustainable products. | Immediately after exposure to intervention and product selection task, assessed during 1-time online study visit | 
| Descriptive Norms | Participants' belief that most shoppers purchase environmentally sustainable foods when shopping for groceries. Likert responses are on a 1 to 5 scale, from Strongly disagree (coded as 1) to Strongly agree (coded as 5), with higher scores representing higher belief that most shoppers purchase environmentally sustainable foods. | Immediately after exposure to intervention and product selection task, assessed during 1-time online study visit |