Do social norms play a role in explaining the impact on food selection of increasing the proportion of healthier food available?

Increasing the relative availability of healthier vs. less-healthy food: Exploring the role of social norms

Status

Recruiting

Phases

Unknown

Study type

Interventional

Source

ISRCTN

Registry ID

ISRCTN10512908

Enrollment

2619

Registered

2020-01-31

Start date

2020-02-03

Completion date

Unknown

Last updated

2020-05-25

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Unhealthy diet Not Applicable

Interventions

The online and lab parts of the study will be conducted simultaneously. Online Study: Mixed design, with 3x2 between-subjects conditions (3 availability conditions x 2 shelf fullness

Group 2: 50% healthier & 50% less-healthy options, fuller shelves

Group 3: 25% healthier & 75% less-healthy options, fuller shelves

Group 4: 75% healthier & 25% less-healthy options, emptier shelves

Group 5: 50% healthier & 50% less-healthy options, emptier shelves

Group 6: 25% healthier & 75% less-healthy options, emptier shelves The primary endpoint is the perceived percentage of sales accounted for by healthier (over less-healthy) options.

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: 1. Adults aged over 18 years 2. Currently residing within the UK

Exclusion criteria

Exclusion criteria: None

Design outcomes

Primary

Measure	Time frame
Online Study: Perceived percentage of sales of healthier (over less-healthy) products measured using the slider questions on the Qualtrics platform Lab Study: Food selection, measured by observing the selection of food (healthier or less healthy) from the tray during the study	—

Secondary

Measure	Time frame
Online study: Selection of products during the study	—

Countries

United Kingdom

Outcome results

None listed

Source: ISRCTN (via WHO ICTRP) · Data processed: Feb 4, 2026