Impact of health warning labels and calorie information on the selection and purchasing of alcohol
| ISRCTN | ISRCTN10313219 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN10313219 |
| Secondary identifying numbers | Alcohol_purchasing_HWL_protocol v1.6 |
- Submission date
- 17/08/2021
- Registration date
- 18/08/2021
- Last edited
- 11/09/2024
- Recruitment status
- No longer recruiting
- Overall study status
- Completed
- Condition category
- Other
Plain English summary of protocol
Background and study aims
Many people exceed the current recommended guidelines for alcohol consumption in the UK. As well as immediate health effects, drinking too much alcohol has been linked to long-term illnesses such as liver diseases (e.g. cirrhosis) and cancers (including breast cancer and bowel cancer). One promising intervention is through improving alcohol health warning labels (HWLs). The aim of this study is to estimate the impact of presenting health warning labels, alone and in combination with calorie information, on the number of alcohol units that are selected and purchased online.
Who can participate?
Adults over the age of 18 years who drink beer or wine at least weekly and regularly purchase alcohol online at Tesco
What does the study involve?
Participants from the research agency's (Roots Research) panel of participants will first be contacted by email and invited to complete the initial screening questionnaire and given information on the study. If eligible, participants will be sent a link to the online drink selection task. The selection task includes 64 drink options including beer, cider, wine, alcohol-free beer, alcohol-free cider, alcohol-free wine and soft drinks. Depending on the allocated condition the alcoholic drinks will contain different labels or display no label (1. image-and-text HWL and calorie information, 2. text-only HWL and calorie information, 3. calorie information only, 4. image-and-text HWL only, 5. text-only HWL only, 6. no HWL or calorie information). Participants select all the drinks for adults in their household that they would like to purchase in their next online Tesco shop. Once the selection task is complete, participants add the selected items to their Tesco basket and send details of their next delivery slot to the research team. On the delivery day, participants send their itemised proof of purchase to researchers.
What are the possible benefits and risks of participating?
Participants will be paid standard market research panel rates for participating in this study. There are no known risks of participating in the study.
Where is the study run from?
1. University of Cambridge (UK)
2. University of Bristol (UK)
When is the study starting and how long is it expected to run for?
February 2021 to March 2022
Who is funding the study?
Wellcome Trust (UK)
Who is the main contact?
Dr Natasha Clarke
n.clarke@bathspa.ac.uk
Contact information
Scientific
Behaviour and Health Research Unit
University of Cambridge
Cambridge
CB2 0SR
United Kingdom
 ORCID ID |
0000-0003-2375-4510 |
|---|---|
| n.clarke@bathspa.ac.uk |
Study information
| Study design | Randomized between-subjects 3 x 2 factorial design |
|---|---|
| Primary study design | Interventional |
| Secondary study design | Randomised controlled trial |
| Study setting(s) | Internet/virtual |
| Study type | Prevention |
| Participant information sheet | Not available in web format, please use the contact details to request a participant information sheet |
| Scientific title | Impact of health warning labels and calorie information on the selection and purchasing of alcohol: an online experimental study |
| Study objectives | Presenting health warning labels (HWLs) on alcoholic drinks will reduce the number of alcohol units selected. The impact of calorie information on the number of alcohol units selected, and any interaction between HWLs and calorie information, will also be explored. |
| Ethics approval(s) | Approved 16/03/2021, Cambridge Psychology Research Ethics Committee (17 Mill Lane, Cambridge, CB2 1RX, UK; +44 (0)1223 (7)66876; Cheryl.Torbett@admin.cam.ac.uk), ref: PRE.2020.155 |
| Health condition(s) or problem(s) studied | Excess alcohol consumption |
| Intervention | Participants will be randomly assigned to one of six conditions in an experiment with a between-subjects 3 (HWL: image-and-text HWL, ii. text-only HWL, iii. no HWL) x 2 (calorie information: present vs absent) factorial design. Randomisation will be online through an algorithm in the Qualtrics survey platform. Participants will view i. a beer, cider and soft drink selection, and ii. a wine and soft drink selection. Alcoholic drinks will be labelled according to the six conditions: 1. Image-and-text HWL and calorie information 2. Text-only HWL and calorie information 3. Calorie information only 4. Image-and-text HWL only 5. Text-only HWL only 6. No HWL or calorie information Non-alcoholic drinks will display calorie labels in the calorie label groups. Within the HWL groups, eight different variants of image-and-text HWLs and six different variants of text-only HWLs will be used to increase variety, maximise engagement and likelihood of the impact of at least one HWL across our sample, and is also based on tobacco guidelines specifying rotating warnings are most effective (Hammond, 2009). The specific warnings used are based on previous studies highlighting these HWLs as being most effective in increasing negative emotions (Pechey et al., 2020) and decreasing the odds of selecting alcohol (Clarke, Pechey, et al., 2020). Calorie information will be given per bottle or can if the total volume of the container is 568 ml or less, or by glass (250 ml) if the volume is over 568 ml (i.e. 1 pint or less). |
| Intervention type | Behavioural |
| Primary outcome measure | Number of alcohol units selected (with an intention to purchase). Participants will be aware that they will be required to purchase the drink items chosen in the selection task and send proof of this to the research team. Therefore, the primary outcome of selection will be made in the context of intention to purchase and participants will provide evidence of this behaviour. Units of alcohol – a measure of pure alcohol in a drink with one unit being 10 ml or 8 g of pure alcohol - will be calculated for all drinks that are >0% ABV (i.e. alcoholic and alcohol-free drinks). |
| Secondary outcome measures | 1. Number of alcoholic drinks selected, calculated from the selection task data immediately, i.e. whilst participants are exposed to the labelling intervention 2. Number of non-alcoholic drinks selected, calculated from the selection task data immediately, i.e. whilst participants are exposed to the labelling intervention 3. Total number of drinks selected, calculated from the selection task data immediately, i.e. whilst participants are exposed to the labelling intervention 4. Proportion of total drinks selected that are alcoholic, calculated by dividing the number of alcoholic drinks selected by the total number of drinks immediately, i.e. whilst participants are exposed to the labelling intervention 5. Number of alcohol units purchased, calculated from the purchasing data (i.e. from proof of purchase) immediately after the selection task 6. Number of alcoholic drinks purchased, calculated from the purchasing data (i.e. from proof of purchase) immediately after the selection task 7. Number of non-alcoholic drinks purchased, calculated from the purchasing data (i.e. from proof of purchase) immediately after the selection task 8. Total number of drinks purchased, calculated from the purchasing data (i.e. from proof of purchase) immediately after the selection task 9. Proportion of total drinks purchased that are alcoholic, calculated by dividing the number of alcoholic drinks purchased by the total number of drinks immediately after the selection task |
| Overall study start date | 01/02/2021 |
| Completion date | 12/03/2022 |
Eligibility
| Participant type(s) | Healthy volunteer |
|---|---|
| Age group | Adult |
| Lower age limit | 18 Years |
| Sex | Both |
| Target number of participants | 600 |
| Total final enrolment | 615 |
| Key inclusion criteria | 1. Aged 18 years or over 2. Current Tesco online customer 3. Regularly consume alcohol – beer, cider and/or wine (i.e., at least once a week) 4. Regularly purchase alcohol – beer, cider and/or wine – online at Tesco (i.e., at least once a month, minimum £20 monthly spend on these drinks) 5. Willing to select drinks from 64 options, shown in an online task, to purchase in next online shop at Tesco (note: options will include different brands of beer, cider, wine, alcohol-free beer, alcohol-free cider, alcohol-free wine and soft drinks available at Tesco; no additional drinks from these categories should be added to the Tesco shop) 6. Willing to complete online shop at Tesco, book a delivery (or Click and Collect) slot, and send the details to the research team within 48 hours of the drink selection task 7. Willing to send proof of purchase (i.e., itemised receipt) to the research team within 48 hours of delivery or collection date 8. Have a Tesco delivery or collection address in England or Wales 9. Able to complete study on a computer or tablet (not mobile phone) |
| Key exclusion criteria | Does not meet the inclusion criteria |
| Date of first enrolment | 24/08/2021 |
| Date of final enrolment | 01/03/2022 |
Locations
Countries of recruitment
- England
- United Kingdom
Study participating centre
Brighton
BN2 9QA
United Kingdom
Sponsor information
University/education
School of Clinical Medicine
Box 111 Cambridge Biomedical Campus
Cambridge
CB2 0SP
England
United Kingdom
| Phone | +44 (0)1223 769291 |
|---|---|
| researchgovernance@medschl.cam.ac.uk | |
| Website | https://researchgovernance.medschl.cam.ac.uk/undertaking-health-research-in-the-united-kingdom/research-sponsorship/ |
"ROR" |
https://ror.org/013meh722 |
Funders
Funder type
Research organisation
Private sector organisation / Trusts, charities, foundations (both public and private)
- Alternative name(s)
- Wellcome, WT
- Location
- United Kingdom
Results and Publications
| Intention to publish date | 01/05/2022 |
|---|---|
| Individual participant data (IPD) Intention to share | Yes |
| IPD sharing plan summary | Stored in publicly available repository |
| Publication and dissemination plan | 1. The protocol and the detailed statistical analysis plan will be pre-registered on the Open Science Framework: https://osf.io/w5xf8/ 2. Planned submission of the main results of this study for publication in a peer-reviewed journal 3. Dissemination of the results to the public, policymakers and other researchers through targeted social media |
| IPD sharing plan | Anonymised participant-level data will be uploaded to the University of Cambridge data repository and on the Open Science Framework project page (https://osf.io/w5xf8/). This data will be open access. This will be uploaded upon publication of the study. Participants are informed of this before providing consent (see participant information sheet) – “At the end of the study your data would become “open data”. This means that it would be stored in an online database so that it is publicly available.” All aspects of the General Data Protection Regulation, Data Protection Act 2018 and the Freedom of Information Act 2000 will be adhered to. All personal data will be treated as confidential. |
Study outputs
| Output type | Details | Date created | Date added | Peer reviewed? | Patient-facing? |
|---|---|---|---|---|---|
| Preprint results | 22/07/2022 | 18/08/2022 | No | No | |
| Protocol (other) | 24/11/2020 | 18/08/2022 | No | No | |
| Dataset | 17/07/2023 | 11/09/2024 | No | No | |
| Results article | 01/08/2023 | 11/09/2024 | Yes | No |
Editorial Notes
11/09/2024: Publication reference and dataset added.
18/08/2022: The following changes were made to the trial record:
1. A link to the unpublished protocol was added.
2. A link to preprint results was added.
06/06/2022: The contact email was updated.
18/03/2022: The overall trial end date was changed from 01/03/2022 to 12/03/2022. Total final enrolment number added.
17/08/2021: Trial's existence confirmed by the Cambridge Psychology Research Ethics Committee.
