The MOSEXY trial: mobile phone intervention for sexual health in youth—a pragmatic randomised controlled trial to evaluate the effect of a smartphone application on sexual health in youth in Stockholm, Sweden

An estimated 350 million cases of STIs occur globally each year. In Sweden, Chlamydia is the most common STI with approximately 30 000 cases annually, disproportionally affecting youth. National surveys report low condom use among youth. Smartphone coverage is high among this tech-savvy group. In collaboration with youth, we developed an interactive smartphone application comprising games, peer experiences and information snippets to promote condom use. OBJECTIVES: To evaluate in a randomised controlled trial, the effectiveness of this smartphone application to improve condom use among youth in Stockholm, Sweden. METHODS: This two-arm, individually randomised controlled trial was implemented through the Youth Health Clinics (YHC) in Stockholm, Sweden. Youth aged 18–23 years, who owned a smartphone and had ≥2 sexual partners during the past 6 months were eligible. The intervention delivered the interactive elements described above over 180 days. The control group received a ‘dummy’ application. Both groups received standard of care at the YHC. The primary outcome was proportion of consistent (100%) self-reported condom use at 6 months. Secondary outcomes included self-reported number of partners, occurrence of STIs/pregnancy and STI tests during the study period. An intention-to-treat approach was used. RESULTS: 214 and 219 youth were randomised to the intervention and control groups, respectively. Consistent condom use was reported for 32/214 (15.0%) in the intervention group and for 35/219 (16.0%) in the control group (OR 0.9, 95% CI 0.5 to 1.6). No significant differences in secondary outcomes were seen. CONCLUSION: We were unable to detect an effect of the intervention. Future research should focus on targeting different subgroups within the overall risk group, with tailored mHealth interventions. The potential for such interventions in settings where sexual health services are unavailable should be evaluated. TRIAL REGISTRATION NUMBER: ISRCTN13212899.