Effect of a text message intervention to reduce hazardous drinking among injured patients discharged from a trauma ward: a randomized controlled trial

Screening and brief intervention for hazardous alcohol use in trauma care settings is known to reduce alcohol intake and injury recidivism, but is often not implemented due to resource constraints. Brief interventions delivered by mobile phone could overcome this challenge. This study aimed to evaluate the effect of a mobile phone text message intervention (YourCall(TM)) on hazardous drinkers admitted for an injury. The parallel two-group, single-blind, randomised controlled trial enrolled 598 injured patients aged 16–69 years identified as medium-risk drinkers at recruitment. The intervention group (n = 299) received 16 text messages incorporating brief intervention principles in the 4 weeks following discharge from hospital. Controls (n = 299) received usual care and one text message acknowledging participation in the trial. The primary outcome was the difference in hazardous alcohol use (assessed using AUDIT-C) between study groups at 3 months, with the maintenance of effect examined at 6 and 12 months’ follow-up. Data were analysed using a mixed-effects model for repeated measures. Both groups had similar baseline features. Compared to controls, hazardous drinking was significantly lower in the intervention group at 3 months and maintained over the 12-month follow-up period (least squares mean difference in AUDIT-C scores: −0.322; 95% CI: −0.636, −0.008; p = 0.04). The intervention effect was similar among Māori (New Zealand’s indigenous population) and non-Māori (interaction p = 0.59), and among younger (16–29 years) and older (30–69 years) patients (p = 0.77). The effectiveness of this intervention reflects the potential of low cost, scalable mobile health technologies to overcome common barriers in implementing alcohol harm reduction strategies following injury.