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

NCT04340791 | Completed

• 1 other identifier: 803194 1B3
• Study Type: interventional
• Target: 1,000
• Locations: 1 country
• Sites: 1

Brief 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.

Conditions

Diet, Healthy; Food Selection

Keywords

availability; labelling; food choice; socio-economic position

Outcome Measures

Primary Outcomes (1)

• 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 Outcomes (6)

• Total energy of the food items purchased (kcal)

  20 minutes (the time frame denotes time taken to make the food shopping task online and there is no follow up)

• Energy from total sugar (% of total energy)

  20 minutes (the time frame denotes time taken to make the food shopping task online and there is no follow up)

• Energy from saturated fatty acids (SFA) (% of total energy)

  20 minutes (the time frame denotes time taken to make the food shopping task online and there is no follow up)

• Salt content (g/100g)

  20 minutes (the time frame denotes time taken to make the food shopping task online and there is no follow up)

• Proportion of lower energy density food items in the basket of foods purchased

  20 minutes (the time frame denotes time taken to make the food shopping task online and there is no follow up)

Other Outcomes (2)

• Validity

  5 minutes (the time frame denotes time taken to fill in the debriefing questionnaire and there is no follow up)

• Kcal influence

  5 minutes (the time frame denotes time taken to fill in the debriefing questionnaire and there is no follow up)

Study Arms (4)

Default proportion & no labelling

NO INTERVENTION

No intervention: Default proportion condition (33% lower energy density items - 67% higher energy density items). Lower energy density items will be defined as lower ED ≤ median of ED distribution within a food category. No labelling.

Default proportion & labelling

EXPERIMENTAL

When energy density of a food item ≤ median of energy density distribution within a food category, "healthier choice" badges will be added to the food item pictures on the online supermarket. Instructions will introduce the badges to the participants as "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."

Behavioral: Labelling

Increased proportion & no labelling

EXPERIMENTAL

The proportion of lower energy density items vs. higher energy density items will be reversed (67% lower - 33% higher) relative to the default proportion condition (33% lower - 67% higher). Lower energy density items will be defined as lower ED ≤ median of ED distribution within a food category.

Behavioral: Increased proportion of lower energy density items

Increased proportion & labelling

EXPERIMENTAL

The proportion of lower energy density items vs. higher energy density items will be reversed (67% lower - 33% higher) relative to the default proportion condition (33% lower - 67% higher). Lower energy density items will be defined as lower ED ≤ median of ED distribution within a food category. When energy density of a food item ≤ median of energy density distribution within a food category, "healthier choice" badges will be added to the food item pictures on the online supermarket. Instructions will introduce the badges to the participants as "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."

Behavioral: Increased proportion of lower energy density items; Behavioral: Labelling

Interventions

Increased proportion of lower energy density items BEHAVIORAL

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.

Increased proportion & labelling; Increased proportion & no labelling

Labelling BEHAVIORAL

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."

Default proportion & labelling; Increased proportion & labelling

Eligibility Criteria

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

You may qualify if:

• 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

You may not qualify if:

• 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)

Sponsors & Collaborators

• University of Liverpool: lead

Study Sites (1)

University of Liverpool

Liverpool, Merseyside, L69 7ZA, United Kingdom

Location

MeSH Terms

Conditions

Food Preferences

Condition Hierarchy (Ancestors)

Feeding Behavior; Behavior

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: April 7, 2020
• First Posted: April 10, 2020
• Study Start: April 13, 2020
• Primary Completion: April 13, 2020
• Study Completion: May 13, 2020
• Last Updated: November 3, 2020

Record last verified: 2020-11

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ICF
• Time Frame: On publication, indefinitely
• Access Criteria: Open website

Locations

GB (1)