Healthy promotions in discount retail
Reducing the Availability of Discretionary Items in SHops (RADISH trial)
The Problem
Families are increasingly reliant on the community food sector, including food banks, pantries and social supermarkets. However, the nutritional profile of foods and beverages in these environments may be sub-optimal. Exposing individuals facing economic hardship to obesogenic shopping environments may further perpetuate known socioeconomic disparities in diet-related illness.
Working with Community Shop, a social supermarket that redistributes quality surplus foods and beverages to individuals facing economic hardship, this trial will determine whether reducing the availability of targeted unhealthy items has a beneficial effect on the nutritional composition of members shopping baskets.
Research question
Does reducing the availability of targeted unhealthy items in Community Shops affect the nutritional composition of members’ shopping baskets?
The Intervention
We will decrease the absolute and relative availability of target product categories within Community Shops by ~40%. The target product categories are: sweet baked goods, sweet biscuits and bars, carbonated/fizzy/sparkling drinks, sweets and confectionery, and crisps. Availability interventions are proposed to work through three mechanisms: increasing the probability that a preferred option is purchased, changing perceptions regarding the popularity of foods and beverages (that is, social norms), and/or reducing the effort needed (cognitive cost) to resist certain foods or beverages. Availability interventions are low agency, making few demands on individuals, which may be important to maximise the efficacy in individuals facing economic hardship.
Setting
Community Shop is a surplus food social supermarket which serves about 8,000 members across 12 shops located in socioeconomically deprived areas of Athersley, Beechwood, Bradford, Goldthorpe, Grimsby, Halton, Kirkdale, Knottingley, Lambeth, Leicester, Scarborough and Warrington. It's a social enterprise affiliated with Company Shop, providing discounted quality food through large end-of-shelf-life donations, to individuals receiving means-tested benefits. Their goal is to reduce food wastage and combat local food insecurity, while also supporting members through their Community Hub and Kitchen services.
Theory of Change
Please click here for our Theory of Change for this trial.
Key Outcomes
1. Primary Outcomes: Proportion of calories (kcal) in a basket derived from High Fat, Salt, or Sugar (HFSS) products.
2. Secondary Outcomes: Secondary outcomes that we will measure as part of the intervention involve:
- Proportion of calories (kcal) in a basket from target product categories.
- Total basket HFSS calories (kcal).
- Total basket target product category calories (kcal).
- Total basket calories (kcal).
- Total basket spend (£).
We will also determine the cost-effectiveness of the intervention and model the effects on public health and environmental outcomes. Moreover, we will undertake a process evaluation to determine members’ and Community Shop’s perspective of the intervention.
Evaluation design
A stepped-wedge design will be conducted to evaluate the intervention. The twelve shops will be randomly assigned to a sequence, with two shops per sequence. Intervention fidelity checks will be conducted regularly during the control and intervention periods.
DAta collection
We will analyse transaction data, provided by Community Shop, and assign nutritional information to foods and beverages using barcodes and semantic similarity algorithms.
Process evaluation
The London School of Hygiene and Tropical Medicine will lead the process evaluation. The goal of the process evaluation is to understand members’ perspectives of the intervention through focus groups (recruiting up to 25 members) and Community Shop employees’ perspectives through 1-1 interviews (including up to 6 shop managers, the Executive Chairman, the Director of Operations, the Head of Operations and the Head of Impact). Members will be recruited in-person and opportunistically during LSHTM shop visits, while Community Shop employees will be approached to participate directly by email. Member focus groups and staff 1-1 interviews will be conducted shortly after completion of the trial.
Governance
The study was reviewed and approved by Oxford’s Central University Research Ethics Committee.
proposed outputs
An academic publication
Our Team
-
David Dearlove
Senior Researcher
-
Darren Hilliard
Researcher
-
Terpsi Panayotidis
Researcher
Key Stakeholders
Community Shop Management, Staff and Members.
Target population
Individuals facing economic hardship.
Timeline
The trial will run from 14th May to 6th August.