COVID-19 studies are our top priority. For all other trials, there is a 4-week delay in processing a trial submitted/resubmitted to the ANZCTR and additional delays for updates of registered trials. We appreciate your patience.

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been endorsed by the ANZCTR. Before participating in a study, talk to your health care provider and refer to this information for consumers
Trial registered on ANZCTR


Registration number
ACTRN12620000582954
Ethics application status
Approved
Date submitted
17/04/2020
Date registered
20/05/2020
Date last updated
20/05/2020
Date data sharing statement initially provided
20/05/2020
Date results information initially provided
20/05/2020
Type of registration
Retrospectively registered

Titles & IDs
Public title
Effect of protective behavioural strategies on the risk of alcohol-related harm in Australian drinkers.
Scientific title
Effect of protective behavioural strategies on the risk of alcohol-related harm in Australian drinkers.
Secondary ID [1] 300970 0
APP1142620
Universal Trial Number (UTN)
U1111-1250-5246
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Alcohol-related harm 317007 0
Alcohol consumption 317008 0
Condition category
Condition code
Public Health 315169 315169 0 0
Health promotion/education

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Participants were exposed to messages that encouraged the use of protective behavioural strategies. Three protective behavioural strategies were tested (i) keep count of your drinks, (ii) decide on a drinks limit and stick to it, and (iii) say no to an offer of an unwanted alcoholic drink. In intervention conditions 1-3, participants were exposed to one of these messages. Participants viewed three images that depicted the messages being displayed on mock promotional materials in the context of everyday situations (on a drinks coaster, poster, and smartphone screen).

Some participants were also shown an existing social marketing campaign video advertisement on the harms associated with alcohol, and a recommendation to not exceed more than two standard drinks on any day. In intervention conditions 4-6, participants were shown this video prior to being shown one of the three messages.

In intervention condition 7, participants were only shown the video without an accompanying message. Condition 8 was an active control condition. Participants in this condition were shown messages that encouraged positive lifestyle behaviours unrelated to alcohol consumption (e.g., increase your physical activity).
Conditions:
1. Message (keep count of your drinks)
2. Message (decide on a drinks limit and stick to it)
3. Message (say no to an offer of an unwanted alcoholic drink)
4. Video + Message (keep count of your drinks)
5. Video + Message (decide on a drinks limit and stick to it)
6. Video + Message (say no to an offer of an unwanted alcoholic drink)
7. Video
8. Active Control

Participants were randomly allocated to one of the conditions. The participants individually viewed the images and/or video relevant to their condition over the internet on a personal device (e.g., desktop, laptop, or tablet). The images and/or video were administered to the participants on three separate occasions over six weeks (week 1, week 3, and week 6). Three images displaying the messages were simultaneously administered to the participants over an internet browser. The participants were instructed to click on each image separately to enlarge it, and to read the message contained within that image carefully. They were allowed to do this at their own pace.

The video was also presented over an internet browser. The participants were instructed to adjust their volume so that they could hear the audio clearly and press the play button to view the video. The video was 30 seconds long and was shown to the participant twice consecutively during each administration.
Intervention code [1] 317301 0
Lifestyle
Intervention code [2] 317508 0
Behaviour
Comparator / control treatment
The active control group was exposed to alternative messages that promoted healthy lifestyle behaviours, such as the consumption of fruit and vegetables and increased physical activity. Control participants were randomly allocated to view 2 of 4 heathy lifestyle messages. The messages were displayed on an image relevant to the context of the message. For example, messages promoting a healthy diet were shown alongside fruit and vegetables, and messages promoting physical activity were shown alongside people walking. The messages were administered over the internet and viewed by the participants on their personal devices (e.g., desktop, laptop, or tablet. Participants were instructed to click on the images depicting the messages to enlarge them, and to carefully read the messages. These messages were administered to the control participants on three separate occasions over six weeks (week 1, week 3, and week 6). The control participant were allowed to view the images at their own pace.
Control group
Active

Outcomes
Primary outcome [1] 323434 0
Alcohol consumption, measured using questionnaire items adapted from the Australian Institute of Health and Welfare National Drug Strategy Household Survey (2016).
Timepoint [1] 323434 0
Assessed at the commencement of the intervention, 3 weeks post intervention, and 6 weeks post intervention.
Secondary outcome [1] 381927 0
Frequency of enacting the protective behavioural strategies, measured using a questionnaire designed for this study.
Timepoint [1] 381927 0
Assessed at the commencement of the intervention, 3 weeks post intervention, and 6 weeks post intervention.
Secondary outcome [2] 381928 0
Alcohol-related harms, measured using an adapted version of the brief young adult alcohol consequences questionnaire.

Kahler, C. W., Strong, D. R., & Read, J. P. (2005). Toward efficient and comprehensive measurement of the alcohol problems continuum in college students: The brief young adult alcohol consequences questionnaire. Alcoholism: Clinical and Experimental Research, 29(7), 1180-1189. https://doi.org/10.1097/01.ALC.0000171940.95813.A5
Timepoint [2] 381928 0
Assessed at the commencement of the intervention, 3 weeks post intervention, and 6 weeks post intervention.
Secondary outcome [3] 381930 0
Perceived effectiveness of the protective behavioural strategies, measured using a questionnaire developed for this study.
Timepoint [3] 381930 0
Assessed at the commencement of the intervention and 3 weeks post intervention.
Secondary outcome [4] 382066 0
Barriers to enacting the protective behavioural strategies, measured using a questionnaire designed for this study.
Timepoint [4] 382066 0
Assessed 6 weeks post intervention
Secondary outcome [5] 382102 0
Intended enactment of the protective behavioural strategies, measured using a questionnaire designed for this study.
Timepoint [5] 382102 0
Assessed at the commencement of the intervention, 3 weeks post intervention, and 6 weeks post intervention.
Secondary outcome [6] 382103 0
Attempts to reduce alcohol consumption, measured using a questionnaire designed for this study.
Timepoint [6] 382103 0
Assessed at the commencement of the intervention, 3 weeks post intervention, and 6 weeks post intervention.

Eligibility
Key inclusion criteria
Participants needed to reside in Australia and have consumed alcohol at least 2 times per month over the last 12 months.
Minimum age
18 Years
Maximum age
70 Years
Gender
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Sampling quotas were used to recruit a sample that is representative of the Australian population. If a quota criterion was full, additional participants who fit this criterion were excluded from the study.

Study design
Purpose of the study
Prevention
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Allocation concealment using computer randomisation.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Simple randomisation using a computer software.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s


Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint(s)
Efficacy
Statistical methods / analysis
To determine whether exposure to the messages resulted in behavioural changes, multivariate analyses of covariance will be performed to explore pre to post differences in protective behavioural strategy enactment and alcohol consumption. This analysis will control for baseline enactment levels, potential confounders (e.g., pre-existing beliefs about alcohol), and any chance differences resulting from the randomisation process. A comprehensive model assessing the relationship between drinkers’ exposure to messages encouraging specific protective behavioural strategies, their attitudes towards these strategies, and subsequent alcohol consumption will be developed and tested via structural equation modelling in Mplus.

To detect a significant difference between the 8 examined conditions with a small effect size, a minimum of 200 participants was needed per condition (for a power of .8). The anticipated 'worst case' attrition rate was 50% per time point. The present study had 3 time points, therefore a minimum sample size of 6,400 was required at Time 1 to ensure that the minimum requirement of 1,600 at Time 3 was met.

Regarding the structural equation model, the largest hypothesised model to be tested in the final phase of the study is likely to contain up to 39 individual parameters, a minimum sample size of 780 is required to follow the recommended 20:1 ratio of cases to parameters (Bentler 2013). As such, the sample is more than adequate to run the largest planned structural equation model.

Bentler PM (2013) EQS: Structural Equations Program Manual. LA: BMDP Statistical Software

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
ACT,NSW,NT,QLD,SA,TAS,WA,VIC

Funding & Sponsors
Funding source category [1] 305417 0
Government body
Name [1] 305417 0
National and Medical Research Council
Address [1] 305417 0
16 Marcus Clarke St,
Canberra, ACT, 2601.
Country [1] 305417 0
Australia
Primary sponsor type
Individual
Name
Professor Simone Pettigrew
Address
The George Institute for Global Health
Level 5,
1 King Street
Newtown, NSW, 2042
Country
Australia
Secondary sponsor category [1] 305808 0
Individual
Name [1] 305808 0
Michelle Jongenelis
Address [1] 305808 0
University of Melbourne
Melbourne Centre for Behaviour Change
Grattan Street,
Parkville, Victoria, 3010
Country [1] 305808 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 305738 0
Curtin University Human Research Ethics Committee
Ethics committee address [1] 305738 0
Curtin University
Kent St,
Bentley WA 6102
Ethics committee country [1] 305738 0
Australia
Date submitted for ethics approval [1] 305738 0
03/03/2018
Approval date [1] 305738 0
09/03/2018
Ethics approval number [1] 305738 0

Summary
Brief summary
This study examined whether messages that encourage Australian drinkers to use protective behavioural strategies can successfully reduce their risk of alcohol-related harm. Three protective behavioural strategies were tested that encouraged people to (i) keep count of their drinks, (ii) decide on a drinks limit and stick to it, and (iii) to say no to an offer of an unwanted alcoholic drink. Previous research has shown that these types of messages can influence people's attitudes to alcohol and drinking intentions. The messages were tested in isolation and in combination with an existing social marketing campaign video advertisement on the harms associated with alcohol consumption.

To assess whether the messages were effective, 8021 Australian drinkers were randomly assigned to eight intervention conditions. Participants in each condition completed three surveys over 6 weeks (3 weeks between each survey). Participants in conditions 1-3 were assigned to see one of the three messages, participants in conditions 4-6 saw the alcohol-harms video followed by one of the messages, participants in condition 7 were only exposed to the alcohol-harms video, and condition 8 was an active control condition. Participants were shown their message and/or the video each time they were surveyed. When completing the surveys, the participants also provided information on their demographic characteristics, use of the recommended drinking practices, attitudes to the recommended drinking practices, alcohol consumption, and experiences of alcohol-related harm. Using this information, the study will determine whether participants who were exposed to the messages changed on these outcomes, relative to participants who were not shown messages that encourage protestive behavioural strategies.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 101414 0
Prof Simone Pettigrew
Address 101414 0
The George Institute for Global Health
Level 5,
1 King Street
Newtown, NSW, 2042
Country 101414 0
Australia
Phone 101414 0
+61 2 8052 4624
Fax 101414 0
Email 101414 0
SPettigrew@georgeinstitute.org.au
Contact person for public queries
Name 101415 0
Prof Simone Pettigrew
Address 101415 0
The George Institute for Global Health
Level 5,
1 King Street
Newtown, NSW, 2042
Country 101415 0
Australia
Phone 101415 0
+61 2 8052 4624
Fax 101415 0
Email 101415 0
SPettigrew@georgeinstitute.org.au
Contact person for scientific queries
Name 101416 0
Prof Simone Pettigrew
Address 101416 0
The George Institute for Global Health
Level 5,
1 King Street
Newtown, NSW, 2042
Country 101416 0
Australia
Phone 101416 0
+61 2 8052 4624
Fax 101416 0
Email 101416 0
SPettigrew@georgeinstitute.org.au

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
What supporting documents are/will be available?
No other documents available
Summary results
Have study results been published in a peer-reviewed journal?
No
Other publications
Have study results been made publicly available in another format?
No
Results – basic reporting
Results – plain English summary