Efficacy of a web- and text messaging-based intervention to reduce problem drinking in adolescents: Results of a cluster-randomized controlled trial.
To test the efficacy of a combined web- and text messaging-based intervention to reduce problem drinking in young people compared to assessment only.



Two-arm, parallel-group, cluster-randomized controlled trial with assessments at baseline and 6-month follow up. The automated intervention included online feedback, based on the social norms approach, and individually tailored text messages addressing social norms, outcome expectations, motivation, self-efficacy, and planning processes, provided over 3 months. The main outcome criterion was the prevalence of risky single-occasion drinking (RSOD, defined as drinking at least 5 standard drinks on a single occasion in men and 4 in women) in the past 30 days. Irrespective of alcohol consumption, 1,355 students from 80 Swiss vocational and upper secondary school classes, all of whom owned a mobile phone, were invited to participate in the study. Of these, 1,041 (76.8%) students participated in the study.



Based on intention-to-treat analyses, RSOD prevalence decreased by 5.9% in the intervention group and increased by 2.6% in the control group, relative to that of baseline assessment (odds ratio [OR] = 0.62, 95% confidence interval [CI] = 0.44-0.87). No significant group differences were observed for the following secondary outcomes: RSOD frequency, quantity of alcohol consumed, estimated peak blood alcohol concentration, and overestimation of peer drinking norms.



The intervention program reduced RSOD, which is a major indicator of problem drinking in young people, effectively. (PsycINFO Database Record
Swiss Research Institute for Public Health and Addiction at Zurich University.
Severin
S
Haug
Swiss Research Institute for Public Health and Addiction at Zurich University.
Raquel
R
Paz Castro
Institute of Technology Management, University of St. Gallen.
Tobias
T
Kowatsch
Institute of Technology Management, University of St. Gallen.
Andreas
A
Filler
Swiss Research Institute for Public Health and Addiction at Zurich University.
Michelle
M
Dey
Swiss Research Institute for Public Health and Addiction at Zurich University.
Michael P
MP
Schaub
D000293:Adolescent; D000294:Adolescent Behavior / Q000523:psychology*; D000328:Adult; D000437:Alcoholism / Q000517:prevention & control* / Q000523:psychology; D001521:Behavior Therapy / Q000379:methods*; D016000:Cluster Analysis; D030141:Feedback, Psychological; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D009042:Motivation; D010379:Peer Group; D015995:Prevalence; D012649:Self Concept; D013557:Switzerland; D017216:Telemedicine / Q000379:methods*; D060145:Text Messaging; D016896:Treatment Outcome; D000066608:Underage Drinking / Q000517:prevention & control* / Q000523:psychology; D055815:Young Adult