Web-based brief personalized feedback intervention in a non-treatment seeking population of heavy drinkers, a randomized controlled trial

Introduction: Compelling evidence exists for the efficacy of face-to-face brief interventions for reducing heavy drinking. However, the evidence for the efficacy of web-based brief interventions is less consistent. In a Danish context, the feasibility and efficacy of a web-based brief intervention targeting heavy drinkers has not been tested.
Objective: To examine whether a web-based personalized feedback intervention and web-based self-help material resulted in lowering of self-reported alcohol use in a non-treatment seeking population of heavy drinkers (defined as weekly alcohol consumption above the Danish sensible drinking limits (14 units = 168 grams of alcohol for women, 21 units = 252 grams for men)).
Methods: Before participating in a Danish Health Examination survey, participants completed a web-based questionnaire.
Screening of 54,158 adults led to inclusion of 1,381 heavy drinkers, who were randomized into a brief personalized feedback group (normative feedback) (n=476), a group receiving self-help material (information about health consequences of exceeding recommended drinking limits) (n=450), or a control group (no information) (n=455). Outcome measure was self-reported alcohol consumption.
Results: Follow-up took place after six/12 months on 873/1066 persons. At six and 12 months follow-up, the difference in weekly alcohol use between the three groups was non-significant (P=0,18 / P=0,47). At six months follow-up, a completers analysis showed significant differences between the control- and the personalized feedback group (2.6 standard drinks, P=0.01). In terms of feasibility, the success of the study was acceptable as 41% accepted participation and 70% were followed up.
Discussion: We found no evidence that a brief personalized feedback intervention or self-help material could lead to a reduction in self-reported alcohol consumption. A completers analysis provides preliminary support for the efficacy of a personalized feedback intervention. Web-based interventions for heavy drinkers are feasible but further evaluations of their efficacy and effectiveness are required.