title: Combining motivational and volitional approaches to reducing excessive alcohol consumption in pre-drinkers: a theory-based intervention protocol.
abstract: BACKGROUND
  Pre-drinking refers to the consumption of alcohol at home or a private residence prior to attending a subsequent social event. We present the study protocol of an online theory-based intervention to reduce pre-drinking and related harm in pre-drinking undergraduates, using behavior change techniques targeting the motivational and volitional phases of behaviour.
  
  
  METHODS
  A fully randomized 2 (autonomy support: present vs. absent) x 2 (implementation intention: present vs. absent) between-participants design will be used to ascertain the effectiveness of the intervention in reducing pre-drinking alcohol consumption and alcohol-related harm. Participants will complete a range of theory-based measures prior to being allocated to one of the four experimental conditions. Four weeks later, participants will complete a follow-up questionnaire comprised of theoretical and behavioral measures.
  
  
  METHODS
  The main and interactive effects of the intervention components in reducing our primary dependent variables, namely, pre-drinking alcohol consumption and alcohol-related harm at four-week follow-up will be tested. Baseline alcohol consumption and demographic information will be included in the analysis as covariates.
  
  
  CONCLUSIONS
  This online intervention is the first to be developed to reduce pre-drinking alcohol consumption, a behaviour linked to increased risk of alcohol-related harm. The intervention targets motivational and volitional components of the behaviour change process and is therefore likely to lead to greater reductions in pre-drinking alcohol consumption and experience of alcohol-related harm compared to either approach in isolation. If successful, the intervention can be implemented across various contexts and in populations where pre-drinking is prevalent.
  
  
  BACKGROUND
  ACTRN12614001102662 . Registered 16 October 2014.
authors.affiliation: Health Psychology & Behavioural Medicine Research Group, School of Psychology and Speech Pathology, Curtin University, Perth, Australia.
authors.forename: Kim M
authors.initials: KM
authors.lastname: Caudwell
authors.affiliation: Health Psychology & Behavioural Medicine Research Group, School of Psychology and Speech Pathology, Curtin University, Perth, Australia.
authors.forename: Barbara A
authors.initials: BA
authors.lastname: Mullan
authors.affiliation: Health Psychology & Behavioural Medicine Research Group, School of Psychology and Speech Pathology, Curtin University, Perth, Australia.
authors.forename: Martin S
authors.initials: MS
authors.lastname: Hagger
mesh_terms: D000293:Adolescent; D000328:Adult; D000428:Alcohol Drinking / Q000453:epidemiology*; D000437:Alcoholism / Q000517:prevention & control*; D001521:Behavior Therapy / Q000379:methods*; D005260:Female; D006801:Humans; D033182:Intention; D008297:Male; D009042:Motivation; D011582:Psychological Theory; D012107:Research Design; D012959:Socioeconomic Factors; D013334:Students; D014495:Universities; D055815:Young Adult