Condition category
Mental and Behavioural Disorders
Date applied
09/12/2019
Date assigned
12/12/2019
Last edited
17/12/2019
Prospective/Retrospective
Retrospectively registered
Overall trial status
Completed
Recruitment status
No longer recruiting

Plain English Summary

Background and study aims
There is has been little research on whether selling smaller portions of alcoholic drinks in pubs and bars reduces the total amount consumed. This study aims to investigate whether adding a two-third pint option for beer and cider sold on tap or removing the largest serving size for a glass of wine reduces the amount that is drunk.

Who can participate?
Licensed premises that offer beer and/or wine and are willing to change the serving sizes of beer and/or wine that they offer.

What does the study involve?
Licenced premises who agree to introduce a 2/3 pint serving size for all of the beer, cider and ale they available on tap will do so for a period of at least 4 weeks. Premises will also be asked to inform customers of the 2/3 pints option by putting signs up.
Licenced premises who agree to remove the 250-ml serving for glasses of wine will do so for a period of at least 4 weeks. Premises will be asked to remove mention of the 250-ml serving from menus and signs as necessary.
Sales data will be collected from bars for a period of at least 12 weeks, covering 4 weeks of business as usual, 4 weeks of the intervention and 4 weeks of going back to business as usual.

What are the possible benefits and risks of participating?
A possible benefit of participating is the opportunity to contribute to a better understanding of how the serving sizes of beer and wine affect sales. Student bars could also contribute to the NUS initiative ‘Alcohol Impact' for safe drinking in students. Licenced premises may benefit from publicity in taking part in this research once the results have been published, but can choose to stay anonymous if they wish. There is no change for the customers except the serving sizes, so there is no risk or benefit to visiting premises participating in the study.

Where is the study run from?
Institute of Public Health, University of Cambridge (UK)

When is the study starting and how long is it expected to run for?
April 2019 to July 2020

Who is funding the study?
The Wellcome Trust

Who is the main contact?
Professor Theresa Marteau, tm388@medschl.cam.ac.uk.

Trial website

Contact information

Type

Scientific

Primary contact

Prof Theresa Marteau

ORCID ID

http://orcid.org/0000-0003-3025-1129

Contact details

Institute of Public Health
University of Cambridge
Robinson Way
CB2 0SR.
Cambridge
CB2 0SR
United Kingdom
01223 762567
tm388@medschl.cam.ac.uk

Additional identifiers

EudraCT number

Nil known

ClinicalTrials.gov number

Nil known

Protocol/serial number

Nil known

Study information

Scientific title

Modifying the range of serving sizes in bars and restaurants to reduce sales of alcohol: a field study

Acronym

Study hypothesis

1. Introducing the option for two-thirds of a pint for beer and cider reduces the amount of beer and cider sold.
2. Removing the largest available serving of a glass of wine (250 ml or 175 ml) reduces the amount of wine sold.

Ethics approval

Approved 02/08/2019, Psychology Research Ethics Committee of the University of Cambridge (School of the Biological Sciences, 17 Mill Lane, Cambridge, CB2 1RX; +44 (0)1223 766876; cheryl.torbett@admin.cam.ac.uk), ref: PRE.2019.035

Study design

Cross-over study

Primary study design

Interventional

Secondary study design

Cross-over study

Trial setting

Community

Trial type

Prevention

Patient information sheet

Not available in web format, please use contact details to request a participant information sheet.

Condition

Excessive alcohol consumption

Intervention

Intervention 1: Adding a two-thirds pint serving size
Sites will add a two-thirds pint serving size for all beers and ciders available on tap. The two-thirds pint will be offered in addition to the existing one pint and half-pint serving sizes, with proportionate pricing as far as is possible i.e. with a price which is linear-by-volume between the pint and half-pint sizes. Sites will choose two-thirds pint glasses to fit with their existing glassware, to be provided by the researchers. Bars will be allowed to keep the glassware after the study.
As part of the intervention, sites will adopt a range of strategies in keeping with their existing practices to draw customers’ attention to the new two-thirds pint option, including information on menus, signs behind the bar and prompting by bar staff when customers are ordering their drink. These practices will be described but not controlled.

Intervention 2: Removing the largest serving size for glasses of wine
Sites will reduce their range of serving sizes for glasses of wine by removing the largest serving size for a glass of wine in their existing range. This will either be 250 ml or 175 ml, with 125 ml sizes always available in keeping with current regulations for selling alcohol in licensed premises. Menus and signage will be updated to reflect this change.

The study has a multiple treatment reversal design with at least three consecutive 4-week periods as follows: ABA, where A represents the baseline periods during which standard serving sizes will be served and B represents the intervention periods in which the range of serving sizes will be modified. Willing sites will complete two additional 4-week periods (BA, resulting in ABABA).
Sites agreeing to implement both interventions will first complete the agreed number of reversals for intervention 1 followed by the agreed number of reversals for intervention 2 (or vice versa).

Intervention type

Behavioural

Phase

Drug names

Primary outcome measure

Intervention 1:
Daily volume (in ml) of beer and cider purchased (including on tap, bottle or can), measured using electronic records of sales

Intervention 2:
Daily volume (in ml) of wine sold (including by the glass, bottle and carafe), measured using electronic records of sales

Sales will be recorded for 12 weeks, including 4 weeks of business as usual before the intervention, 4 weeks of the intervention and 4 weeks going back to business as usual after the intervention.

Secondary outcome measures

1. Daily volume of beer and cider sold by serving size (pint, ½ pint, 2/3 pint, bottle sizes, can sizes) measured using electronic records of sales
2. Daily volume of wine purchased by serving size (125 ml, 175 ml, 250 ml, carafe, 750 ml bottle) measured using electronic records of sales
3. Daily volume of alcohol sold excluding beer and cider (during intervention 1) or wine (during intervention 2) measured using electronic records of sales
4. Daily revenue from food and alcoholic and non-alcoholic drink measured using electronic records of sales
5. Daily number of transactions measured using electronic records of sales
6. Daily amount of beer and cider (during intervention 1) or wine (during intervention 2) sold in units of alcohol (in cases where it is practical to extract this information from electronic sales data) measured using electronic records of sales

Sales will be recorded for 12 weeks, including 4 weeks of business as usual before the intervention, 4 weeks of the intervention and 4 weeks going back to business as usual after the intervention.

Overall trial start date

02/04/2019

Overall trial end date

31/07/2020

Reason abandoned (if study stopped)

Eligibility

Participant inclusion criteria

1. Licensed premises that sell beer (and/or cider) on tap in sizes larger than two-thirds of a pint (for intervention 1)
2. Willing to introduce a two-thirds pint serving size for all beer and cider available on tap at a proportionate price (for intervention 1)
3. Sell wine by the glass in serving sizes greater than 125 ml (i.e. 175 ml or 250 ml) (for intervention 2)
4. Willing to cap the serving size of a glass of wine (for intervention 2)
5. Have an electronic point of sale (EPOS) till system to record daily sales of all drinks and their served sizes

Participant type

All

Age group

Adult

Gender

Both

Target number of participants

Customers of 23 licensed premises

Participant exclusion criteria

Does not meet inclusion criteria

Recruitment start date

27/08/2019

Recruitment end date

29/02/2020

Locations

Countries of recruitment

United Kingdom

Trial participating centre

Institute of Public Health
University of Cambridge Robinson Way
Cambridge
CB2 0SR
United Kingdom

Sponsor information

Organisation

University of Cambridge

Sponsor details

Cambridge Research Office
16 Mill Lane
Cambridge
CB2 1SB
Cambridge
CB2 1SB
United Kingdom
Cambridge
CB2 1SB
United Kingdom
01223 7766362
Jo.Dekkers@admin.cam.ac.uk

Sponsor type

University/education

Website

https://www.research-operations.admin.cam.ac.uk/about-us/contact-us

Funders

Funder type

Research organisation

Funder name

Wellcome Trust

Alternative name(s)

Funding Body Type

private sector organisation

Funding Body Subtype

International organizations

Location

United Kingdom

Results and Publications

Publication and dissemination plan

The findings from this study will be published in at least one scientific journal in 2020 and made available open access. They will also be presented at one or more scientific meetings. The data will be made available for sharing via the University of Cambridge Research Data Repository or Open Science Framework online data repository once the findings have been published.

IPD sharing statement:
The study will not use individual-level data: the unit of randomisation, data collection and analysis will be individual public houses and bars. The datasets generated and/or analysed during the current study will be stored in a publicly available repository. All study data will be anonymised using a unique numeric identifier. At the appropriate time, the anonymous study datasheet will be locked and deposited on the University of Cambridge Data Repository. If a publican decides that they do not want their data to be used after their participation they have the right to request that their data are withdrawn from the study. They can request this up to two weeks after study completion. Publicans are made aware of this prior to giving consent to their participation in the study and to the use of their anonymised study data.

Intention to publish date

31/12/2020

Participant level data

Not provided at time of registration

Basic results (scientific)

Publication list

Publication citations

Additional files

Editorial Notes

17/12/2019: Internal review. 13/12/2019: Internal review. 11/12/2019: Trial's existence confirmed by the University of Cambridge Psychology Research Ethics Committee.