The Effect of a Descriptive Norm Promoting Vegetable Selection in a Workplace Restaurant Setting: an Observational Study

NCT ID: NCT02603263

Last Updated: 2015-11-11

Basic Information

• Recruitment Status: COMPLETED
• Total Enrollment: 9445 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2015-02-28
• Study Completion Date: 2015-08-31

Brief Summary

Encouraging individuals to eat fruit and vegetables is difficult. However, recent evidence suggests that using social-based information might help. For instance, it has been shown that if people think that others are eating lots of fruit and vegetables, that they will consume more food to match the 'norm'.The purpose of this study was to determine whether social norm messages could be used to enhance vegetable purchases in workplace restaurants, in an observational study.

Detailed Description

In this study the investigators hypothesised that placing posters containing social norm messages promoting vegetable consumption in three workplace restaurants, would increase the purchase of meals with vegetables, and that this effect would be sustained over time. The investigators recruited three restaurants to this study. For two weeks (Pre-intervention phase) the investigators used till receipts to monitor the number of meals sold with or without vegetables at baseline. For the following two weeks (Intervention phase) the investigators placed social norms posters around the three restaurants, while continuing to collect till receipts. After this, the posters were removed, and receipts were monitored for a final two weeks (Post-intervention).

Conditions

Eating Behaviour

Study Groups

Workplace Restaurant Customers

1 Group (Workplace Restaurant Customers) across 3 sites (data to be combined at end of study)

Study consists of three phases:

1. Pre Intervention

2. Intervention

3. Post Intervention

All phases lasted two weeks and included monitoring till receipts for meals (these were automatically generated and held on the tills electronically). The intervention phase consisted of posters being displayed in the restaurants, featuring a Social Norms Poster.

Social Norms Poster

Intervention Type: OTHER

A poster containing a social norms message: "Most people here choose to eat vegetables with their lunch"

Interventions

Social Norms Poster

A poster containing a social norms message: "Most people here choose to eat vegetables with their lunch"

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• Purchase of a meal at one of the restaurants

Exclusion Criteria

• None

• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Economic and Social Research Council, United Kingdom

OTHER

Sponsor Role: collaborator

C H & Co Ltd.

INDUSTRY

Sponsor Role: collaborator

University of Birmingham

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Jason M Thomas, PhD

Role: PRINCIPAL_INVESTIGATOR

University of Birmingham

Locations

University of Birmingham

Birmingham, West Midlands, United Kingdom

Countries

United Kingdom

References

Thomas JM, Ursell A, Robinson EL, Aveyard P, Jebb SA, Herman CP, Higgs S. Using a descriptive social norm to increase vegetable selection in workplace restaurant settings. Health Psychol. 2017 Nov;36(11):1026-1033. doi: 10.1037/hea0000478. Epub 2017 May 25.

Reference Type: DERIVED

PMID: 28541071 (View on PubMed)

Other Identifiers

UBirmingham-SNS7

Identifier Type: -

Identifier Source: org_study_id