Article Text

Download PDFPDF

Original article
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
  1. Anna Maria Nielsen1,
  2. Ayesha De Costa2,
  3. Kristina Gemzell-Danielsson1,
  4. Gaetano Marrone2,
  5. Jens Boman3,
  6. Mariano Salazar2,
  7. Vinod Diwan2
  1. 1Womens and Childrens Health, Karolinska Institutet, Stockholm, Sweden
  2. 2Public Health Sciences, Karolinska Institutet, Stockholm, Sweden
  3. 3Department of Clinical Microbiology, Umea Universitet Medicinska fakulteten, Umea, Sweden
  1. Correspondence to Anna Maria Nielsen, Womens and Childrens Health, Karolinska Institutet, Stockholm 171 77, Sweden; anna.nielsen.1{at}


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.

  • sexual health
  • adolescent
  • behavioural interventions
  • condoms
  • sexual behaviour

This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See:

View Full Text

Statistics from


  • Handling editor Catherine H Mercer

  • Contributors All authors authorised the final version of the manuscript. All authors contributed to the design of the study, the write up of the study protocol, supported implementation and provided oversight. The corresponding author, AMN, was involved in the recruitment and allocation process at the different sites. Statistical analysis/interpretation and writing-up the manuscript were performed by AMN, ADC and GM. All authors contributed substantially in writing and critical review of the manuscript. The corresponding author attests that all listed authors meet authorship criteria and that no others meeting the criteria have been omitted.

  • Funding The project was funded by FORTE – Swedish Research Council for Health, Working life and Welfare.

  • Disclaimer The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

  • Competing interests None declared.

  • Patient consent for publication Not required.

  • Ethics approval The study protocol was ethically approved by the ethical review board of the Regional Ethical Review Board, Stockholm (reference number: 2017/651-31/4 & 2017/1880-32).

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Data availability statement Data are available on reasonable request.

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.