title: The economic impact of project MARS (motivating adolescents to reduce sexual risk).
abstract: OBJECTIVE
  The purpose of this study was to economically evaluate Project MARS (Motivating Adolescents to Reduce Sexual Risk; T. J. Callahan, E. A. Montanaro, R. E. Magnan, & A. D. Bryan, 2013, "Project MARS: Design of a multi-behavior intervention trial for justice-involved youth," Translational Behavioral Medicine, Vol. 3, pp. 122-130), an ongoing, randomized, sexual-risk-reduction intervention for justice-involved youth. We consider the effect of including viral STIs in the economic analysis, and explore the impact of the MARS intervention on the perceived cost of acquiring STIs to justice-involved youth.
  
  
  METHODS
  206 participants, ages 14 to 18, participated in a sexual-risk-reduction intervention that included screening and treatment for chlamydia and gonorrhea. A Bernoulli probability model was used to estimate averted STIs attributable to the MARS intervention. The economic benefit of averted STIs was monetized using the direct medical cost of treatment. In addition, we used a contingent valuation (willingness-to-pay) model to investigate the impact of the Project MARS on participants' perceived cost of acquiring an STI.
  
  
  RESULTS
  Using the standard outcome domains typically used to evaluate STI interventions, Project MARS resulted in a reduction of $2.08 in direct medical costs for every $1 spent. When viral STIs were added to the economic model, a considerable increase in averted direct medical costs ($2.68 for every $1 spent) was found. Preliminary contingent valuation estimates suggest that participants' willingness-to-pay for averted STIs significantly increased after receiving the MARS intervention.
  
  
  CONCLUSIONS
  From an economic perspective, Project MARS is a worthwhile program to adopt. Future attention should be given to the impact of behavioral interventions on viral infections.
authors.affiliation: Department of Economics, University of New Mexico, Albuquerque, NM 87131-0001, USA.
authors.forename: Bern C
authors.initials: BC
authors.lastname: Dealy
authors.forename: Brady P
authors.initials: BP
authors.lastname: Horn
authors.forename: Tiffany J
authors.initials: TJ
authors.lastname: Callahan
authors.forename: Angela D
authors.initials: AD
authors.lastname: Bryan
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior / Q000523:psychology*; D003362:Cost-Benefit Analysis; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007604:Juvenile Delinquency; D008297:Male; D018803:Models, Economic; D009042:Motivation; D015397:Program Evaluation; D040242:Risk Reduction Behavior; D012725:Sexual Behavior / Q000523:psychology*; D012749:Sexually Transmitted Diseases / Q000191:economics / Q000517:prevention & control*