Increased Proportion of Lower Energy Density Items vs. Nutritional Labelling at an Online Supermarket

Diet, Healthy Clinical Trial

Official title:

Effectiveness of Information-based Versus Structural Interventions on Food Choices by Socioeconomic Position: a Randomized Controlled Trial in an Experimental Online Supermarket

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT04340791
• Other study ID #: 803194 1B3
• Status: Completed
• Phase: N/A
• Start date: April 13, 2020
• Est. completion date: May 13, 2020

Study information

• Verified date: November 2020
• Source: University of Liverpool
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

This study will be a 2x2 randomised controlled trial with information-based intervention (no labelling / labelling) and structural intervention (default proportion / increased proportion of lower energy density food items) as between-subject factors and energy density (kcal/g) of food purchases during an online supermarket-shopping task as dependent variable. This study will use an online supermarket platform developed to mimic an online supermarket website and participants will be asked to complete a shopping task using a pre-determined shopping list of 10 items.

Description:

See attached protocol documents.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 1000
• Est. completion date: May 13, 2020
• Est. primary completion date: April 13, 2020
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• United Kingdom residents

• Aged = 18 years

• Fluent in English

• Have access to a computer and Internet

• Responsible for a substantial proportion of household grocery shopping

Exclusion Criteria:

• Unable to provide informed consent and to comply with the study requirements

• Any dietary restriction (vegetarian, vegan, gluten-free, sugar-free, dairy or lactose free, food allergy, other)

Related Conditions & MeSH terms

• Diet, Healthy
• Food Selection

Intervention

Behavioral:
• Increased proportion of lower energy density items
The proportion of lower energy density vs. higher energy density items will be reversed (67% lower - 33% higher) relative to the default proportion condition (D and DL) (33% lower - 67% higher). Lower energy density items will be defined as lower energy density = median of energy density distribution within a food category.
• Labelling
When energy density of an item = median of ED distribution within a food category, "healthier choice" badges will be added to the food item pictures on the online supermarket. Instructions when logging-into the platform will introduce the badges to the participants: "In the online supermarket, the green tick allows you to see which products (e.g. muesli) in each product category (e.g. cereals) are healthier choices with fewer calories per gram than most other products in the same category."

Locations

Country	Name	City	State
United Kingdom	University of Liverpool	Liverpool	Merseyside

Sponsors (1)

Lead Sponsor	Collaborator
University of Liverpool

Country where clinical trial is conducted

United Kingdom, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Other	Validity	Mean of item "I would normally buy [the 10 items on the shopping list]" for all the food items coded as: 1 = Never; 2 = Very rarely; 3 = Rarely; 4 = Occasionally; 5 = Frequently; 6 = Very frequently.	5 minutes (the time frame denotes time taken to fill in the debriefing questionnaire and there is no follow up)
Other	Kcal influence	Answer to the item "The choices I made during online shopping were influenced by how many calories I thought were in the options available." coded as: 1 = Strongly disagree; 2 = Disagree; 3 = Slightly disagree; 4 = Neutral; 5 = Slightly agree; 6 = Agree; 7 = Strongly agree	5 minutes (the time frame denotes time taken to fill in the debriefing questionnaire and there is no follow up)
Primary	Mean ED of the food items purchased (kcal/100g)	Calculated as the sum of the energy of the purchased items (kcal) divided by the sum of their weight (g) and multiplied by 100.	20 minutes (the time frame denotes time taken to make the food shopping task online and there is no follow up)
Secondary	Total energy of the food items purchased (kcal)	Calculated as the sum of the energy of the purchased items (kcal)	20 minutes (the time frame denotes time taken to make the food shopping task online and there is no follow up)
Secondary	Energy from total sugar (% of total energy)	Calculated as the percentage of total energy of the purchased items from total sugar	20 minutes (the time frame denotes time taken to make the food shopping task online and there is no follow up)
Secondary	Energy from saturated fatty acids (SFA) (% of total energy)	Calculated as the percentage of total energy of the purchased items from SFA	20 minutes (the time frame denotes time taken to make the food shopping task online and there is no follow up)
Secondary	Salt content (g/100g)	Calculated as the sum of the salt content of the purchased items (g) divided by the sum of their weight (g) and multiplied by 100.	20 minutes (the time frame denotes time taken to make the food shopping task online and there is no follow up)
Secondary	Proportion of lower energy density food items in the basket of foods purchased	Lower energy density items will be defined as = median of energy density distribution within a food category	20 minutes (the time frame denotes time taken to make the food shopping task online and there is no follow up)
Secondary	Cost (GPB)	Calculated as the sum of the prices of the purchased items	20 minutes (the time frame denotes time taken to make the food shopping task online and there is no follow up)