The effect of modifying serving sizes of beer and wine on alcohol consumption
| ISRCTN | ISRCTN33258531 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN33258531 |
| ClinicalTrials.gov (NCT) | Nil known |
| Clinical Trials Information System (CTIS) | Nil known |
| Protocol serial number | Nil known |
| Sponsor | University of Cambridge |
| Funder | Wellcome Trust |
- Submission date
- 09/12/2019
- Registration date
- 12/12/2019
- Last edited
- 04/04/2023
- Recruitment status
- No longer recruiting
- Overall study status
- Stopped
- Condition category
- Mental and Behavioural Disorders
Plain English summary of protocol
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.
Contact information
Scientific
Institute of Public Health, University of Cambridge, Robinson Way, CB2 0SR.
Cambridge
CB2 0SR
United Kingdom
 ORCID ID |
0000-0003-3025-1129 |
|---|---|
| Phone | 01223 762567 |
| tm388@medschl.cam.ac.uk |
Study information
| Primary study design | Interventional |
|---|---|
| Study design | Cross-over study |
| Secondary study design | Cross-over study |
| Study type | Participant information sheet |
| Scientific title | Modifying the range of serving sizes in bars and restaurants to reduce sales of alcohol: a field study |
| Study objectives | 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(s) | 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 |
| Health condition(s) or problem(s) studied | 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 |
| Primary outcome measure(s) |
Intervention 1: |
| Key secondary outcome measure(s) |
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 |
| Completion date | 31/07/2020 |
| Reason abandoned (if study stopped) | Pandemic |
Eligibility
| Participant type(s) | All |
|---|---|
| Age group | Adult |
| Sex | All |
| Target sample size at registration | 23 |
| Key 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 |
| Key exclusion criteria | Does not meet inclusion criteria |
| Date of first enrolment | 27/08/2019 |
| Date of final enrolment | 29/02/2020 |
Locations
Countries of recruitment
- United Kingdom
- England
Study participating centre
Robinson Way
Cambridge
CB2 0SR
United Kingdom
Results and Publications
| Individual participant data (IPD) Intention to share | No |
|---|---|
| IPD sharing plan summary | Not provided at time of registration |
| IPD sharing plan | 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. |
Study outputs
| Output type | Details | Date created | Date added | Peer reviewed? | Patient-facing? |
|---|---|---|---|---|---|
| Participant information sheet | Participant information sheet | 11/11/2025 | 11/11/2025 | No | Yes |
Editorial Notes
04/04/2023: Internal review.
16/03/2021: This study was terminated on the 20th March 2021 due to the COVID-19 pandemic. In error, this message was not posted on that date. Pre-pandemic responses to the interventions may differ post-pandemic so any additional data will be collected as part of a new study
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.
