A randomised experiment of health, cost and social norm message frames to encourage acceptance of swaps in a simulation online supermarket

Gao, Zhifeng, Bunten, Amanda, Porter, Lucy, Sanders, Jet G., Sallis, Anna, Payne Riches, Sarah, Van Schaik, Paul, González-Iraizoz, Marta, Chadborn, Tim and Forwood, Suzanna (2021) A randomised experiment of health, cost and social norm message frames to encourage acceptance of swaps in a simulation online supermarket. PLOS ONE, 16 (2). e0246455. ISSN 1932-6203

Published Version
Available under the following license: Creative Commons Attribution.

Download (809kB) | Preview
Official URL: https://doi.org/10.1371/journal.pone.0246455


Offering lower-energy food swaps to customers of online supermarkets could help to decrease energy (kcal) purchased and consumed. However, acceptance rates of such food swaps tend to be low. This study aimed to see whether framing lower-energy food swaps in terms of cost savings or social norms could improve likelihood of acceptance relative to framing swaps in terms of health benefits. Participants (n = 900) were asked to shop from a 12-item shopping list in a simulation online supermarket. When a target high-energy food was identified in the shopping basket at check-out, one or two lower-energy foods would be suggested as an alternative (a “swap”). Participants were randomised to only see messages emphasising health benefits (fewer calories), cost benefits (lower price) or social norms (others preferred this product). Data were analysed for 713 participants after exclusions. Participants were offered a mean of 3.17 swaps (SD = 1.50), and 12.91% of swaps were accepted (health = 14.31%, cost = 11.49%, social norms = 13.18%). Swap acceptance was not influenced by the specific swap frame used (all p > .170). Age was significantly and positively associated with swap acceptance (b = 0.02, SE = 0.00, p < .001), but was also associated with smaller decreases in energy change (b = 0.46, SE = .19, p = .014). Overall, offering swaps reduced both energy (kcal) per product (b = -9.69, SE = 4.07, p = .017) and energy (kcal) per shopping basket (t712 = 11.09, p < .001) from pre- to post-intervention. Offering lower-energy food swaps could be a successful strategy for reducing energy purchased by customers of online supermarkets. Future research should explore alternative solutions for increasing acceptance rates of such swaps.

Item Type: Journal Article
Keywords: Food, Socioeconomic aspects of health, Fats, Behavioral and social aspects of health, Internet, Obesity, Body weight, Linear regression analysis
Faculty: Faculty of Science & Engineering
Depositing User: Lisa Blanshard
Date Deposited: 25 Feb 2021 11:56
Last Modified: 28 Jan 2022 13:43
URI: https://arro.anglia.ac.uk/id/eprint/706360

Actions (login required)

Edit Item Edit Item