Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12613000573752
Ethics application status
Approved
Date submitted
15/05/2013
Date registered
21/05/2013
Date last updated
20/11/2019
Date data sharing statement initially provided
20/11/2019
Type of registration
Prospectively registered

Titles & IDs
Public title
Increasing Motivation and Self-control to Reduce Alcohol Consumption among Undergraduate Students
Scientific title
An Intervention Using Process and Outcome Mental Simulation Exercises and Self-control Training to Reduce Alcohol Consumption among Undergraduate Students
Secondary ID [1] 282507 0
Nil
Universal Trial Number (UTN)
Nil
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
alcohol consumption 289164 0
Condition category
Condition code
Public Health 289489 289489 0 0
Other public health

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Participants are randomly allocated into 4 groups. The trial will involve two independent conditions using a 2 (mental simulation: mental simulation vs. control irrelevant visualization exercise) x 2 (self-control training: difficult training vs. active ‘control’ easy training) design. For the mental simulation intervention, participants randomized to receive the intervention will be required to imagine the steps they will take to change their alcohol consumption known as ‘process mental simulation’ and imagine how they would feel on achieving the outcomes known as 'outcome mental simulation'. Participants will be given a process mental simulation script adapted from Pham and Taylor’s (1999) article. The targeted behaviour is adapted as drinking within recommended safe limits. Participants need to follow instructions, read the script, and rehearse it with eyes closed under quiet conditions. Then, they need to write down their responses in the space provided and remember it throughout the research period. Written responses will be content analysed to check for compliance with the task. This mental simulation task should take no longer than 10 minutes. Participants randomized to the control condition will not receive any relevant visualization exercise but will be asked to imagine a recent visit to the cinema or shopping centre to maintain equivalent information load to the active mental simulation condition for 10 minutes.

For the self-control training, participants randomized to receive the difficult intervention will be required to complete a computerised response-inhibition task (incongruent version of the ‘Stroop colour-naming’ task). Participants randomized to receive the ‘control’ easy training condition will receive an easy version of the response inhibition task (congruent version of the ‘Stroop colour-naming’ task. This response-inhibition task should take no longer than 5 minutes. Participants will complete the task to which they have been assigned immediately after the visualization task in the initial session and then repeat this on a daily basis throughout the intervention period of four weeks.The response inhibition task system will be used to monitor participants’ adherence by logging each trial and uploading participant responses to a remote server via internet providing compliance data with the training task. Also, four reminder emails or text messages will be sent to prompt participants to practice the Stroop task.

The design is therefore 2 (IV1) x 2 (IV2) design with 4 arms. Arm 1: mental simulation & difficult self-control training incongruent Stroop task; Arm 2: mental simulation & ‘control’ easy self-control training congruent Stroop task (congruent version of Stroop task does not affect response inhibition); Arm 3: irrelevant control visualization task & difficult self-control training incongruent Stroop task; Arm 4: irrelevant control visualization task & ‘control’ easy training congruent Stroop task (active control group).
Intervention code [1] 287160 0
Lifestyle
Intervention code [2] 287161 0
Behaviour
Comparator / control treatment
Active control.
The control group will be asked to perform irrelevant control visualisation task (to maintain information load with the intervention group but with no effect on motivation toward alcohol consumption) and a 'control' easy training congruent Stroop task (that does not affect response inhibition).
Control group
Active

Outcomes
Primary outcome [1] 289590 0
alcohol consumption measured by participant self-report at follow-up. Participants will be asked to report number of units of standard drinks they had consumed and the number of occasions when they binge drank weekly over the previous four weeks. Participants reported their drinking behaviour by answering the questionnaire. The measure is based on the time-line follow back technique to obtain the estimates of drinking (Sobell et al., 1979).
Timepoint [1] 289590 0
4 weeks post-intervention
Secondary outcome [1] 302822 0
self-reported levels of self-control by participants are the proposed mechanisms for the effect of the self-control manipulation. It is measured by state self-control capacity measure (Ciarocco, Twenge, Muraven, & Tice, 2011). This is a psychometric instrument with scaled responses to items (e.g. I feel discouraged) with responses made on 7-point Likert scales ranging from 1 (no true) to 7 (very true).
Timepoint [1] 302822 0
4 weeks post-intervention
Secondary outcome [2] 302823 0
Self-reported levels of self-efficacy by participants are proposed mechanisms for the effect of the mental simulation manipulation. It is measure by standardised measures of the Theory of Planned Behaviour used in previous study (Hagger, Lonsdale, & Chatzisarantis, 2011). This is a psychometric measure asking participants to rate their confidence with respect to reducing alcohol intake (e.g. “How motivated are you to keep your alcohol drinking to within safe limits on each individual occasion or session over the next four weeks?”) with responses made on 6-point scales ranging from 1 (not at all motivated) to 6 (extremely motivated).
Timepoint [2] 302823 0
4 weeks post-intervention

Eligibility
Key inclusion criteria
All participants should be over 18 years old, non-abstinent with respect to alcohol consumption and undergraduate students
Minimum age
18 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
non alcohol drinkers

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)
Participants will be recruited via advertising and online recruitment using a dedicated online participant pool for undergraduate psychology students incentivised by course credit or a prize draw for shopping vouchers. Participants will be allocated to a study condition on recruitment according to a permuted block randomisation schedule drawn up a priori generated using a random number generator. Block randomisation is used to ensure equal numbers per group. The conditions in the schedule will be labelled A-D and the experimenter administering the intervention will be blinded to the condition content by having an independent researcher code the content of the intervention conditions and allocate them to study information packs labelled A-D accordingly. The experimenter will be aware of the conditions only after the intervention.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
permuted block randomisation will be used generated using a random number generator (www.randomizer.org)
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s
The people administering the treatment/s

Intervention assignment
Factorial
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
Data will be analysed using a 2 (mental simulation condition: mental simulation vs. no mental simulation) x 2 (response inhibition self-control training condition: challenging (incongruent) vs. easy (congruent)) factorial between-groups analysis of covariance (ANCOVA) with self-reported alcohol consumption at follow-up as the dependent variable and baseline self-reported alcohol consumption as the covariate. Assuming a medium effect size based on a previous meta-analysis from the current laboratory (Hagger et al., 2010) and setting power at .80 and alpha at .05, we anticipate a total sample size of 128 participants.

Recruitment
Recruitment status
Stopped early
Data analysis
No data analysis planned
Reason for early stopping/withdrawal
Participant recruitment difficulties
Date of first participant enrolment
Anticipated
24/05/2013
Actual
24/05/2013
Date of last participant enrolment
Anticipated
31/08/2015
Actual
30/09/2015
Date of last data collection
Anticipated
Actual
30/09/2015
Sample size
Target
128
Accrual to date
Final
70
Recruitment in Australia
Recruitment state(s)
WA

Funding & Sponsors
Funding source category [1] 287289 0
University
Name [1] 287289 0
curtin university
Country [1] 287289 0
Australia
Primary sponsor type
Individual
Name
Ging Ging Wong
Address
Curtin University, Kent St Bentley WA 6102
Country
Australia
Secondary sponsor category [1] 286042 0
None
Name [1] 286042 0
Address [1] 286042 0
Country [1] 286042 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 289266 0
Curtin University School of psychology and Speech Pathology Ethics Committee
Ethics committee address [1] 289266 0
Kent St Bentley WA 6102
Ethics committee country [1] 289266 0
Australia
Date submitted for ethics approval [1] 289266 0
Approval date [1] 289266 0
18/03/2013
Ethics approval number [1] 289266 0
Psych and SP 2013 - 05

Summary
Brief summary
This experimental study will examine the effectiveness of increasing motivation and self-control to reduce alcohol consumption among undergraduate students..It is proposed that motivation and self-control are two psychological factors that can influence alcohol consumption. Adopting theoretical perspectives from the Pham and Taylor’s (1999) model on mental simulations and the strength model of self-control (Baumeister et al., 1998), people who are motivated via a process mental simulation manipulation and have self-control practice on a Stroop task will be more likely to reduce their alcohol consumption.The aim of this research is to test the hypothesis that individuals who receive motivation and self-control manipulations will have higher reduction in alcohol consumption than a control group comprising individuals that did not receive manipulation. Also, we hypothesise that combined experimental manipulations of motivation and self-control is more effective than either of the motivation and self-control manipulations alone in reducing alcohol consumption
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 40066 0
Prof Martin Hagger
Address 40066 0
Curtin University, Kent St Bentley WA 6102
Country 40066 0
Australia
Phone 40066 0
+61412879953
Fax 40066 0
Email 40066 0
[email protected]
Contact person for public queries
Name 40067 0
Prof Martin Hagger
Address 40067 0
Curtin University, Kent St Bentley WA 6102
Country 40067 0
Australia
Phone 40067 0
+61412879953
Fax 40067 0
Email 40067 0
[email protected]
Contact person for scientific queries
Name 40068 0
Prof Martin Hagger
Address 40068 0
Curtin University, Kent St Bentley WA 6102
Country 40068 0
Australia
Phone 40068 0
+61412879953
Fax 40068 0
Email 40068 0
[email protected]

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 Supporting Document Provided



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
SourceTitleYear of PublicationDOI
EmbaseA theory-based behavior-change intervention to reduce alcohol consumption in undergraduate students: trial protocol.2015https://dx.doi.org/10.1186/s12889-015-1648-y
N.B. These documents automatically identified may not have been verified by the study sponsor.