Web-based self-help for problem drinkers: a pragmatic randomized trial

Aims Self-help interventions for adult problem drinkers in the general population have proved effective. The question is whether this also holds for self-help interventions delivered over the internet. Design We conducted a pragmatic randomized trial with two parallel groups, using block randomization stratified for gender and with follow-up at 6 months. Setting The intervention and trial were conducted online in the Netherlands in 2003-2004. Participants We selected 261 adult problem drinkers from the general population with a weekly alcohol consumption above 210 g of ethanol for men or 140 g for women, or consuming at least 60 g (men) or 40 g (women) at least 1 day a week over the past 3 months. Participants were randomized to either the experimental drinking less (DL) condition or to the control condition (PBA). Intervention DL is a web-based, multi-component, interactive self-help intervention for problem drinkers without therapist guidance. The recommended treatment period is 6 weeks. The intervention is based on cognitive-behavioural and self-control principles. The control group received access to an online psychoeducational brochure on alcohol use (PBA). Outcome measures We assessed the following outcome measures at 6-month follow-up: (i) the percentage of participants who had reduced their drinking levels to within the normative limits of the Dutch guideline for low-risk drinking; and (ii) the reduction in mean weekly alcohol consumption. Findings At follow-up, 17.2% of the intervention group participants had reduced their drinking successfully to within the guideline norms; in the control group this was 5.4% [odds ratio (OR) = 3.66; 95% confidence interval (CI) 1.3-10.8; P = 0.006; number needed to treat (NNT) = 8.5]. The intervention subjects decreased their mean weekly alcohol consumption significantly more than control subjects, with a difference of 12.0 standardized units (95% CI 5.9-18.1; P < 0.001; standardized mean difference 0.40). Conclusions To our knowledge this is one of the first randomized controlled trials on a web-based self-help intervention without therapist guidance for self-referred problem drinkers among the adult general population. The intervention showed itself to be effective in reducing problem drinking in the community.