Internet-based brief personalized feedback intervention in a non-treatment-seeking population of adult heavy drinkers: A randomized controlled trial

Background: internet-based interventions for heavy drinkers show promising results,but existing research is characterized by few studies in nonstudent adult populations and few comparisons with appropriate control groups. objective: to test whether a fully automated internet-based brief personalized feedback intervention and a fully automated internet-based personalized brief advice intervention in a non-treatment-seeking population of heavy drinkers would result in a reduced alcohol intake. methods: we conducted a 3-arm parallel randomized controlled trial in a general population-based sample of heavy drinkers. the 54,157 participants (median age of 58 years) were screened for heavy drinking. of the 3418 participants who had a weekly alcohol consumption above 14 drinks for women and 21 drinks for men,1380 (619 women) consented to take part in the trial and were randomly assigned to an internet-based brief personalized feedback intervention group (normative feedback,n = 476),an internet-based personalized brief advice intervention group (n = 450),or a nonintervention control group (n = 454). follow-up after 6 and 12 months included 871 and 1064 participants,respectively,of all groups combined. the outcome measure was self-reported weekly alcohol consumption. we analyzed the data according to the intention-to-treat principle. to examine changes over time and to account for the multiple time measurements,we used a multilevel linear mixed model. to take attrition into account,we used multiple imputation to address missing data. results: the intervention effect of the internet-based brief personalized feedback intervention,determined as the mean additional difference in changes in alcohol consumption in the internet-based brief personalized feedback intervention compared with the control group,was -1.8 drinks/week after 6 months and -1.4 drinks/week after 12 months; these effects were nonsignificant (95% confidence interval -4.0 to 0.3 at 6 months,-3.4 to 0.6 at 12 months). the intervention effect of the internet-based personalized brief advice intervention was -0.5 drinks/week after 6 months and -1.2 drinks/week after 12 months; these effects were nonsignificant (95% confidence interval -2.7 to 1.6 at 6 months,-3.3 to 0.9 at 12 months). conclusions: in this randomized controlled trial we found no evidence that an internet-based brief personalized feedback intervention was effective in reducing drinking in an adult population of heavy drinkers.