Long‐term effects of a peer‐led Brief Alcohol Screening and Intervention for College Students (BASICS) intervention to reduce alcohol consumption among Spanish university students: A 12‐month randomised controlled trial

BACKGROUND AND AIMS: Harmful alcohol consumption remains widespread among university students and is associated with numerous academic, social and health-related consequences. Peer-led approaches offer a promising strategy to reduce risky drinking in this population. This study evaluated the long-term effects of a peer-led Brief Alcohol Screening and Intervention for College Students (BASICS) program. DESIGN: A parallel two-group randomised controlled trial with a follow-up period of 12 months was conducted. SETTING: The study took place at a university in Spain. PARTICIPANTS: A total of 308 undergraduate students who had engaged in at least one episode of heavy drinking in the previous month were randomly assigned to either the intervention group (n = 154) or the control group (n = 154). INTERVENTION: The intervention group received a single individual session of the peer-delivered BASICS program. The control group received no intervention during the study period. MEASUREMENTS: The primary outcome was the number of alcoholic drinks consumed during a typical week at the 12-month follow-up. Secondary outcomes included weekly drinking at one month, as well as weekend drinking, drinks on the heaviest occasion, binge drinking episodes, peak blood alcohol concentration during a typical week and on the heaviest occasion, alcohol-related consequences, motivation to reduce alcohol use and self-efficacy, all of which were assessed at both 1 and 12 months. FINDINGS: At the primary 12-month follow-up, statistically significant between-group differences were observed for all nine measured outcomes. For the primary outcome, the mean weekly alcohol consumption was 8.93 drinks [95% confidence interval (CI) = 7.7-10.2] in the intervention group and 12.35 drinks (95% CI = 11.1-13.6) in the control group. The between-group difference was 3.42 drinks (95% CI = 1.66-5.18), indicating lower consumption in the intervention group. Among the secondary outcomes, statistically significant differences were also observed for weekend drinking (3.08 drinks, 95% CI = 1.59-4.56), drinks on the heaviest occasion (3.27 drinks, 95% CI = 1.79-4.76), binge drinking frequency (0.93 episodes, 95% CI = 0.54-1.32) and alcohol-related consequences (3.28 points, 95% CI = 1.74-4.82). CONCLUSIONS: Among Spanish college students who had engaged in at least one episode of heavy drinking in the previous month, a single peer-led Brief Alcohol Screening and Intervention for College Students (BASICS) session produced sustained improvements in alcohol use, related consequences, and psychological mediators up to 12 months post-intervention.