BMJ published an RCT in Switzerland of a smartphone app to reduce drinking among university students with unhealthy alcohol use. Quick take: High-quality RCT finds modest but meaningful 7% decrease in drinks per week at 1-year mark for a low-cost, scalable intervention.

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Program:

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• The smartphone app gave personalized feedback on self-reported alcohol use, including comparison to average use by others of same sex and age; feedback on caloric content of user's alcohol consumption and health risks; self-monitoring and goal-setting tools; and other features.

 

Study Design:

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• The RCT sample comprised 1,770 university students with diverse backgrounds at 4 campuses, screened as having unhealthy alcohol use. Based on careful review, this was a well-conducted RCT (e.g., excellent baseline balance, negligible attrition, prespecified outcomes). The treatment group's app usage was high.

 

Findings:

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• On the primary prespecified outcome: The study found a 7% reduction in self-reported number of standard drinks/week at both the 6- and 12-month follow-ups. (At 12 months, the control group averaged 7.59 drinks/week vs 7.04 for the treatment group, a statistically significant difference.)

 

Comment:

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• This impact is modest but I think meaningful, as the app is very low cost and scalable to reach large student populations.

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• Replication RCTs in other countries (ideally with longer-term follow-up and biological samples to validate self-reported alcohol use) would be valuable to hopefully confirm the results and establish their generalizability.