Individual Traits and Food Choice Nudges: Exploring How Socioeconomic and Personal Factors Shape Nudge Effectiveness Across Different Nudge Types
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 607
- 试验地点
- 1
- 主要终点
- Healthiness of Food Choices (basket healthiness)
研究概览
简要总结
This study used a randomized five-condition experiment in a mock online supermarket to investigate whether just-in-time (JIT) food-swap recommendations can improve the healthiness of food choices and whether different types of justification: visibility-only, descriptive/normative language (DNL), social norms, and hedonic enhancement, affect recommendation acceptance and food choice healthiness. The study also examined the psychological mechanisms underlying these effects, focusing on ethe ease of identifying healthy options (EIHO) as a facilitating mechanism and psychological reactance as a potential barrier, and explored whether effects varied by socioeconomic position, food choice motives, and decision-making styles. Ultimately, the study aimed to identify personalization approaches that can make JIT food-swap recommendations effective across the socioeconomic gradient.
详细描述
This study employed a between-subjects design with one factor (JIT justification type) and five levels/conditions: no recommendation; JIT visibility-only (recommendation without justification); DNL; social norm; and hedonic enhancement. Acceptance rate and healthiness of food choices were the primary outcome variables. Participants were randomly assigned to one of the conditions and then completed a hypothetical grocery-shopping task using MAND, a mock supermarket app developed by NAKKO. Psychological reactance and ease of identifying healthier options (EIHO) were included as mediating variables. General decision-making style (GDMS), food choice motive (FCM), education level, and subjective socioeconomic position were included as moderating variables. This study was approved by the Ethical Review Board of the Tilburg School of Humanities and Digital Sciences (Identification code: REDC2023.34abc).
The study was conceptually divided into two models for theoretical clarity. Model 1 (The JIT Presence Mediation Model) focused on the effects of the JIT visibility-only recommendation (versus no JIT) on healthiness of food choices. Model 2 (JIT Justification Type Moderation Model) focused on the effects of JIT justification types (DNL, hedonic enhancement, social norms versus JIT visibility-only recommendation) on acceptance rate. Our hypotheses are visualized in the conceptual models 1 and model 2 and were preregistered at the Open Science Framework (osf.io/y29ha). The hypotheses and models differ from the original preregistration only in their numbering, which was revised to clarify and separate the models, and in minor rewording for clarity.
Aims:
The study aimed to examine the effects of different Just-In-Time food-swap recommendations on healthiness of food choices (model 1) and on acceptance rate (model 2). The study also explored the facilitating (ease of identifying healthier options) and hindering (psychological reactance) underlying mechanisms, and whether they differed by SEP, domain-general (GDMS) and food-specific (FCM) individual characteristics. Lastly, the study aimed to contribute to identifying personalization approaches that could make JIT food swap recommendations effective across the socioeconomic gradient
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
- Single (Participant)
盲法说明
Participants were not informed about in which arm of the study they were allocated.
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
- •being fluent in the Dutch language
- •have a smartphone
排除标准
- •no dietary restrictions
- •not complete the shopping task or final questionnaire
- •very short or long completion times
- •Participants must pass at least one of two attention checks
研究组 & 干预措施
JIT Visibility Only Nudge
An alternative product (image, product name, and price) is suggested in the pop-up, accompanied by a header that reads "Alternative"
干预措施: JIT Visibility Only Nudge (Other)
Descriptive Nutritional Labelling Nudge
This nudge is the same as the JIT visibility only nudge condition, but with an additional text providing health information on the alternative compared to the original choice (e.g., "This product contains less salt").
干预措施: Descriptive Nutritional Labelling Nudge. (Other)
Hedonic Enhancement Nudge
This nudge is the same as the JIT visibility only nudge condition, but with an additional descriptive text (e.g., "Delicious and refreshing"). Furthermore, the product image is replaced with an enhanced version that highlights the product's taste and visual appeal.
干预措施: Hedonic Enhancement Nudge (Other)
Social Norm Nudge
This nudge is the same as the JIT visibility only nudge condition, but with an additional descriptive prompt (e.g., "4 out of 5 people chose this") and a visual representation.
干预措施: Social Norm Nudge (Other)
No Nudge (control)
Participants are not presented with a pop-up showing a suggested alternative. After making their selection, they are immediately routed back to the start screen, where they can click on the next product category.
干预措施: No Nudge (control) (Other)
结局指标
主要结局
Healthiness of Food Choices (basket healthiness)
时间窗: During the retail application session
The healthiness of each participant's final basket (i.e., after the possibility to swap before final checkout) was measured by using the FNS score of each product and calculating the average score of the six products they selected for experimental product categories. The FNS score ranges from -15 to +40. A smaller average FNS score means healthier food choices.
Acceptance rate
时间窗: During the retail application session
Recommendation acceptance rate was measured as the proportion of recommendations accepted during experimental trials, calculated as the number of accepted recommendations divided by the total number of recommendations presented (ranging from 3 to 6).
次要结局
- Ease of Identifying Healthier Options (EIHO)(immediately after the intervention)
- Psychological Reactance(immediately after the intervention)
研究者
Laura Nynke van der Laan
Associate professor
Tilburg University