title: [Analysis on the relationship between condom social norms and unprotected anal intercourse among men who have sex with men in Beijing].
abstract: OBJECTIVE
  To understand the prevalence of and factors associated with unprotected anal intercourse (UAI) among men who have sex with men (MSM) in Beijing.
  
  
  METHODS
  Five hundred MSM were recruited for a survey using Respondent Driven Sampling (RDS) method, from September to October in 2009. A computer-assisted, interviewer-administered questionnaire was used to gather information including demographics, sexual behaviors and condom use social norms (a scaled number). Variables were evaluated by using RDSAT and SAS software.
  
  
  RESULTS
  Mean age of the participants was 30.6 years, with 96.0% of them as Han ethnicity and 68.5% having had at least high school or higher education level. 72.8% of them were unmarried, with 61.7% of them identified themselves as homosexual, 61.2% had > 1 male partners in the past six months, and the prevalence of UAI was 42.0%. Significant bivariate predictors of UAI would include condom use social norms score, role for anal sex with male sex partner, number of male sexual partners in the past 6 months and amount of alcohol consumed. In multivariable analysis, UAI was associated with a higher condom use social norms score (AOR = 1.2, 95%CI: 1.1 - 1.3), receptive anal intercourse (AOR = 2.0, 95%CI: 1.3 - 3.2) and drinking alcohol more than 3 times per month in the past 12 months (AOR = 1.6, 95%CI: 1.1 - 2.5).
  
  
  CONCLUSIONS
  The prevalence of UAI was high in the MSM community in Beijing, suggesting that efforts should be targeting on how to make the condom use a social norm and being promoted.
authors.affiliation: National Center for AIDS/STD Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China.
authors.forename: Song
authors.initials: S
authors.lastname: Fan
authors.forename: Yan-Ming
authors.initials: YM
authors.lastname: Sun
authors.forename: Hong-Yan
authors.initials: HY
authors.lastname: Lu
authors.forename: Xiao-Yan
authors.initials: XY
authors.lastname: Ma
authors.forename: Hai
authors.initials: H
authors.lastname: Yue
authors.forename: Li
authors.initials: L
authors.lastname: Lu
authors.forename: Xiong
authors.initials: X
authors.lastname: He
authors.forename: Wei
authors.initials: W
authors.lastname: Ma
authors.forename: Xue-Feng
authors.initials: XF
authors.lastname: Li
authors.forename: Yan
authors.initials: Y
authors.lastname: Xiao
authors.forename: Yu-Hua
authors.initials: YH
authors.lastname: Ruan
authors.forename: Yi-Ming
authors.initials: YM
authors.lastname: Shao
mesh_terms: D000328:Adult; D000428:Alcohol Drinking; D002681:China; D017280:Condoms / Q000706:statistics & numerical data; D018451:Homosexuality, Male; D006801:Humans; D008297:Male; D015995:Prevalence; D012309:Risk-Taking; D021841:Safe Sex / Q000706:statistics & numerical data*; D012725:Sexual Behavior; D011795:Surveys and Questionnaires; D047568:Unsafe Sex / Q000706:statistics & numerical data*; D055815:Young Adult