Price Promotions on Purchases of Snacks

NCT05098223 | Completed

• 1 other identifier: R65010/RE005
• Study Type: interventional
• Target: 512
• Locations: 1 country
• Sites: 1

Brief Summary

Study Design: Randomised controlled trial Study Participants: Healthy volunteers from the UK Planned Sample Size: 500 Planned Study Period: June - December 2021 Objectives and Outcome Measures:

• Objective: To investigate the effect of promotions on the total number of calories selected
• Measure: Difference in the absolute energy (kcal) of the final basket between the two groups
• Secondary
• To investigate the effect of promotions on the nutritional content of the items selected overall, and across the individual target food categories
• To explore the impact of removing promotions by socioeconomic status Measures:
• Difference in the absolute sugar (g, kcal, %E), salt (g), and saturated fat (g, kcal, %E) of the final basket between the two groups
• Difference in the absolute energy (kcal), sugar (g, kcal, %E), salt (g), and saturated fat (g, kcal, %E) between the two groups across the individual target food categories
• Analyses of the primary and secondary outcomes specified above by gender, age group, ethnic group (White vs Non-White), BMI stratified into \<30 and ≥30kg/m2 groups, education level (lower vs. higher), and household income (lower vs. higher)
• Exploratory outcomes:
• Objective: To investigate the acceptability of the intervention
• Measures: Rating scores and open-ended answers from the follow-up questionnaire

Conditions

Healthy Diet

Outcome Measures

Primary Outcomes (1)

• To investigate the effect of promotions on the total number of calories selected

  Difference in the absolute energy (kcal) of the final basket between the two groups

  1 day (immediately after the shopping task)

Secondary Outcomes (8)

• To investigate the effect of promotions on the nutritional content of the items selected overall, and across the individual target food categories

  1 day (immediately after the shopping task)

• To investigate the effect of promotions on the nutritional content of the items selected overall, and across the individual target food categories

  1 day (immediately after the shopping task)

• To investigate the effect of promotions on the nutritional content of the items selected overall, and across the individual target food categories

  1 day (immediately after the shopping task)

• To investigate the effect of promotions on the nutritional content of the items selected overall, and across the individual target food categories

  1 day (immediately after the shopping task)

• To investigate the effect of promotions on the nutritional content of the items selected overall, and across the individual target food categories

  1 day (immediately after the shopping task)

Other Outcomes (1)

• To investigate the acceptability of the intervention

  1 day (immediately after the shopping task)

Study Arms (2)

Promotions

NO INTERVENTION

Participants in this group will see a version of the website which will reproduce the types and frequency of promotions that can be found in any online supermarket, for example multi-buy offers and temporary price reductions will be applied to a pre-determined percentage of food products within the target categories \[confectionery; biscuits and crackers; crisps, nuts and snacking fruit; cakes and tarts\]. Promotions will be applied to match the current levels and types of promotions on the website of the largest UK retailer present in a specific week, shortly before the study launch.

No promotions

EXPERIMENTAL

All price promotions will be removed so no promotions will be present on any of the products within the target food categories \[confectionery; biscuits and crackers; crisps, nuts and snacking fruit; cakes and tarts\] offered to participants when searching for products.

Behavioral: Intervention to remove price promotions on unhealthy foods when online shopping

Interventions

Intervention to remove price promotions on unhealthy foods when online shopping BEHAVIORAL

Removal of price promotions on unhealthy foods

No promotions

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• UK adults, aged ≥18 years.
• Able to speak and read English.
• Willing and able to give informed consent for participation in the study.
• Having access to a computer and Internet.

You may not qualify if:

• They are following a dairy-free or sugar-free diet.

Sponsors & Collaborators

• University of Oxford: lead

Study Sites (1)

Nuffield Dept of Primary Care Health Sciences

Oxford, Oxfordshire, OX2 6GG, United Kingdom

Location

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
• Masking Details: Investigators will be blinded to intervention allocation and will not be able to manipulate any study parameter following the initial study set up, as all study procedures are taking part in the online platform. The outcome assessment is blinded, as it happens automatically in the online platform. The statistician who will analyse the data will be blinded to intervention allocation. Participants will only be aware of the trial arm that they are exposed to and will be unaware of the other trial arm
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: This is a randomised controlled trial with a parallel design. We will use an experimental online shopping platform to mimic the experience of online grocery shopping. Each participant will be randomised 1:1 to one of two groups and will participate in an online shopping task for about 10 minutes during which they will be exposed to a selection of products including promotions or with no promotions.

Study Record Dates

• First Submitted: September 27, 2021
• First Posted: October 28, 2021
• Study Start: October 29, 2021
• Primary Completion: November 9, 2021
• Study Completion: November 9, 2021
• Last Updated: February 17, 2022

Record last verified: 2021-09

Locations

GB (1)