title: Cross-sectional survey comparing HIV risk behaviours of adolescent and young adult men who have sex with men only and men who have sex with men and women in the U.S. and Puerto Rico.
abstract: OBJECTIVE
  To examine the HIV risk behaviours of men who have sex with men only (MSMO) and men who have sex with men and women (MSMW), aged 12-24 years, in five US cities and in San Juan, Puerto Rico.
  
  
  METHODS
  Data were collected through four annual cross-sectional anonymous surveys at community venues and included questions about sexual partnerships, sexual practices including condom use and substance use. Demographic and risk profiles were summarised for both groups.
  
  
  RESULTS
  A total of 1198 men were included in this analysis, including 565 MSMO and 633 MSMW. There were statistically significant differences between the two groups for many risk factors examined in multivariable models. MSMW were more likely to identify as bisexual, be in a long-term relationship, have a history of homelessness, have ever used marijuana, have ever been tested for HIV and to have been tested for HIV within the past 6 months. MSMW may be more likely to ever exchange sex for money and ever have a sexually transmitted infection than MSMO.
  
  
  CONCLUSIONS
  MSMW were more likely to report several markers of socioeconomic vulnerability or behaviours associated with increased risk for HIV than MSMO. MSMW contribute to HIV prevalence in the USA, and better understanding of the risk profile of this group is essential to understand heterosexual HIV transmission. MSMW, particularly those who identify as bisexual or questioning, may feel uncomfortable participating in programmes that are designed for gay-identified men. Therefore, prevention strategies need to target distinct subgroups that compose the population of MSM.
authors.affiliation: Department of Pediatrics, All Children's Hospital Johns Hopkins Medicine, St Petersburg, Florida, USA.
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Ellen
authors.affiliation: Westat, Rockville, Maryland, USA.
authors.forename: Lauren
authors.initials: L
authors.lastname: Greenberg
authors.affiliation: Department of Pediatrics, Johns Hopkins University, Baltimore, Maryland, USA.
authors.forename: Nancy
authors.initials: N
authors.lastname: Willard
authors.affiliation: Children's National Medical Center, Washington, DC, USA.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Stines
authors.affiliation: Westat, Rockville, Maryland, USA.
authors.forename: James
authors.initials: J
authors.lastname: Korelitz
authors.affiliation: Department of Pediatrics, University of California, San Francisco, San Francisco, California, USA.
authors.forename: Cherrie B
authors.initials: CB
authors.lastname: Boyer
mesh_terms: D000293:Adolescent; D001727:Bisexuality / Q000523:psychology / Q000706:statistics & numerical data*; D003430:Cross-Sectional Studies; D015658:HIV Infections / Q000453:epidemiology / Q000517:prevention & control* / Q000523:psychology; D018451:Homosexuality, Male / Q000523:psychology / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D015995:Prevalence; D011647:Puerto Rico / Q000453:epidemiology; D012307:Risk Factors; D012309:Risk-Taking; D012725:Sexual Behavior / Q000523:psychology / Q000706:statistics & numerical data*; D012747:Sexual Partners / Q000523:psychology; D019966:Substance-Related Disorders / Q000453:epidemiology / Q000517:prevention & control* / Q000523:psychology; D014481:United States / Q000453:epidemiology; D047568:Unsafe Sex / Q000523:psychology / Q000706:statistics & numerical data*; D055815:Young Adult
keywords: ADOLESCENT; HETEROSEXUAL BEHAVIOUR; HIV; SEXUAL BEHAVIOUR; SEXUAL HEALTH