A Randomized Trial of Food Swaps to Improve the Healthfulness and Reduce the Carbon Footprint of Grocery Purchases
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 1,201
- 试验地点
- 2
- 主要终点
- Healthfulness of product selection
研究概览
简要总结
The study aims to determine whether viewing health or climate labels (or both) and receiving recommendations for healthier or more climate-friendly swaps (or both) in an online grocery store environment improves the healthfulness and reduces the carbon footprint of consumers' food and beverage purchases compared to shopping as usual without swap recommendations. The online store will record participants' food selections. Participants will also be asked to complete survey measures.
详细描述
Participants will complete an online between-subjects randomized experiment. The experiment will involve three study visits.
In the first study visit, participants will complete an online grocery store shopping task without intervention. Participants will be given a budget of $50 and asked to shop as they normally would. The store will record participants' food selections. After completing the shopping task, participants will complete an online survey.
Approximately one week later, participants will complete a second study visit with the same instructions. They will be randomized to 1 of 4 conditions (1) health only, 2) climate only, 3) combined health and climate, 4) control. In the health only condition, participants will view labels with nutrition grades and may be directed to swap their selections for healthier items. In the climate only condition, participants will view labels with climate grades and may be directed to swap their selections for more climate-friendly (lower-carbon-footprint) items. In the combined health and climate condition, participants will view labels with health and climate grades and may be directed to swap their selections for healthier or more climate-friendly items. In the control group, participants will not view any labels or swaps. The store will record participants' selections. After completing the shopping task, participants will complete an online survey.
In the third study visit, the participants will maintain their assigned group and will be asked to repeat the same tasks as in the second visit.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Prevention
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Aged 18 years or older
- •Reside in the United States
- •Able to complete a survey in English
- •Have internet access to complete the 3 online study visits
排除标准
- •Under the age of 18
- •Reside outside of the United States
- •Unable to complete a survey in English
- •Do not have internet access to complete the 3 online study visits
研究组 & 干预措施
Health swaps
Labels will be "nutrition grades" for products and replacement swap suggestions will be for items with a better nutrition grade.
干预措施: Health swaps (Behavioral)
Climate swaps
Labels will be "climate grades" for products and replacement swap suggestions will be for items with a better climate grade.
干预措施: Climate swaps (Behavioral)
Combined health and climate swaps
Labels will be "nutrition grades" and "climate grades" for products and replacement swap suggestions will be for items that are better than originally selected products on at least one dimension (nutrition grade or climate grade) and not worse than originally selected products on either dimension.
干预措施: Combined health and climate swaps (Behavioral)
Control
No labels or swaps.
干预措施: Control (Behavioral)
结局指标
主要结局
Healthfulness of product selection
时间窗: Assessed at baseline, 1-week follow-up, and 2-week follow-up
The study will asses healthfulness of participants' selections as the average Ofcom Nutrient Profiling Model score of the products the participants select in the shopping task. The score ranges from 0 to 100, where higher scores are healthier.
Carbon footprint of participants' grocery store selections
时间窗: Assessed at baseline, 1-week follow-up, and 2-week follow-up
The study will assess the carbon footprint of participants' selections, operationalized as the average carbon footprint (in CO2-equivalents) of the products the participants select in the shopping task.
Healthfulness of Product Selection
时间窗: 1-week follow-up (visit 2), and 2-week follow-up (visit 3)
The study will asses healthfulness of participants' selections as the average Ofcom Nutrient Profiling Model score of the products the participants select in the shopping task. The score ranges from 0 to 100, where higher scores are healthier. Outcome values were calculated as each participant's mean across visits 2 and 3. If participants had missing data at one of these visits, data from the non-missing visit was used.
Carbon Footprint of Participants' Grocery Store Selections
时间窗: 1-week follow-up (visit 2), and 2-week follow-up (visit 3)
The study will assess the carbon footprint of participants' selections, operationalized as the average carbon footprint (in CO2-equivalents) of the products the participants select in the shopping task. Outcome values were calculated as each participant's mean across visits 2 and 3. If participants had missing data at one of these visits, the non-missing value was used.
次要结局
- Saturated fat density of participants' grocery selections(Assessed at baseline, 1-week follow-up, and 2-week follow-up)
- Fiber density of participants' grocery selections(Assessed at baseline, 1-week follow-up, and 2-week follow-up)
- Protein density of participants' grocery selections(Assessed at baseline, 1-week follow-up, and 2-week follow-up)
- Total spending on participants' grocery selections(Assessed at baseline, 1-week follow-up, and 2-week follow-up)
- Calorie density of participants' grocery selections(Assessed at baseline, 1-week follow-up, and 2-week follow-up)
- Sugar density of participants' grocery selections(Assessed at baseline, 1-week follow-up, and 2-week follow-up)
- Sodium density of participants' grocery selections(Assessed at baseline, 1-week follow-up, and 2-week follow-up)
- Thinking about health(Assessed at baseline, 1-week follow-up, and 2-week follow-up)
- Thinking about climate impact(Assessed at baseline, 1-week follow-up, and 2-week follow-up)
- Thinking about taste(Assessed at baseline, 1-week follow-up, and 2-week follow-up)
- Injunctive norms to buy foods with low climate impact(Assessed at baseline, 1-week follow-up, and 2-week follow-up)
- Descriptive norms to buy foods with low climate impact(Assessed at baseline, 1-week follow-up, and 2-week follow-up)
- Calorie Density of Participants' Grocery Selections(1-week follow-up (visit 2), and 2-week follow-up (visit 3))
- Sugar Density of Participants' Grocery Selections(1-week follow-up (visit 2), and 2-week follow-up (visit 3))
- Sodium Density of Participants' Grocery Selections(1-week follow-up (visit 2), and 2-week follow-up (visit 3))
- Saturated Fat Density of Participants' Grocery Selections(1-week follow-up (visit 2), and 2-week follow-up (visit 3))
- Fiber Density of Participants' Grocery Selections(1-week follow-up (visit 2), and 2-week follow-up (visit 3))
- Protein Density of Participants' Grocery Selections(1-week follow-up (visit 2), and 2-week follow-up (visit 3))
- Total Spending on Participants' Grocery Selections(1-week follow-up (visit 2), and 2-week follow-up (visit 3))
- Thinking About Health(1-week follow-up (visit 2), and 2-week follow-up (visit 3))
- Thinking About Climate Impact(1-week follow-up (visit 2), and 2-week follow-up (visit 3))
- Thinking About Taste(1-week follow-up (visit 2), and 2-week follow-up (visit 3))
- Negative Emotional Reactions While Shopping(1-week follow-up (visit 2), and 2-week follow-up (visit 3))
- Positive Emotional Reactions While Shopping(1-week follow-up (visit 2), and 2-week follow-up (visit 3))
- Injunctive Norms to Buy Healthy Foods(1-week follow-up (visit 2), and 2-week follow-up (visit 3))
- Descriptive Norms to Buy Healthy Foods(1-week follow-up (visit 2), and 2-week follow-up (visit 3))
- Injunctive Norms to Buy Foods With Low Climate Impact(1-week follow-up (visit 2), and 2-week follow-up (visit 3))
- Descriptive Norms to Buy Foods With Low Climate Impact(1-week follow-up (visit 2), and 2-week follow-up (visit 3))
- Descriptive norms to buy healthy foods(Assessed at baseline, 1-week follow-up, and 2-week follow-up)
- Injunctive norms to buy healthy foods(Assessed at baseline, 1-week follow-up, and 2-week follow-up)
- Negative emotional reactions while shopping(Assessed at baseline, 1-week follow-up, and 2-week follow-up)
- Positive emotional reactions while shopping(Assessed at baseline, 1-week follow-up, and 2-week follow-up)
研究者
Anna Grummon
Assistant Professor
Stanford University