title: [A respondent-driven sampling survey on HIV and risk factors among men who have sex with men in Chongqing].
abstract: OBJECTIVE
  To examine HIV prevalence and related risk factors among men who have sex with men (MSM) in Chongqing, and to explore the feasibility of using respondent-driven sampling (RDS) in the survey.
  
  
  METHODS
  Based on results from formative research, a RDS survey was designed and conducted to collect demographic, behavioral and serologic data. RDSAT was used to calculate point estimation and confidence intervals. SPSS was used for bi-variate analysis using RDSAT exported weighed data. NETDRAW was used to draw network diagram.
  
  
  RESULTS
  Among 617 subjects recruited, the adjusted HIV and syphilis prevalence rates were 16.8% and 10.9%, respectively. 73.0% of the subjects were 20 to 29 years old and 72.9% were officially registered residents of Chongqing. 83.4% were single, with the proportion of students the highest, accounting for 24.6%. During the last six months, 83.4% of them reported ever having anal sex, and 54.0% reported having unprotected anal sex.
  
  
  CONCLUSIONS
  This survey confirmed that Chongqing had a higher reported HIV prevalence among MSM than from other Chinese cities. Comprehensive intervention services were required to address this alarmingly high prevalence, with focus on intervention through internet and those having syphilis infection. RDS seemed one of the effective ways of recruiting hidden MSM populations in Chongqing which had a large population of active MSM who did not frequently visit MSM venues as compared with snowball method.
authors.affiliation: Chongqing Center for Disease Control and Prevention, Chongqing 400042, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Ouyang
authors.forename: Lian-gui
authors.initials: LG
authors.lastname: Feng
authors.forename: Xian-bin
authors.initials: XB
authors.lastname: Ding
authors.forename: Jin-kou
authors.initials: JK
authors.lastname: Zhao
authors.forename: Jing
authors.initials: J
authors.lastname: Xu
authors.forename: Mei
authors.initials: M
authors.lastname: Han
authors.forename: Chao
authors.initials: C
authors.lastname: Zhou
mesh_terms: D000328:Adult; D002681:China / Q000453:epidemiology; D003625:Data Collection / Q000379:methods*; D005240:Feasibility Studies; D015658:HIV Infections / Q000453:epidemiology*; D018451:Homosexuality, Male / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D015999:Multivariate Analysis; D015995:Prevalence; D012307:Risk Factors; D012494:Sampling Studies; D012725:Sexual Behavior / Q000706:statistics & numerical data; D012847:Single Person / Q000706:statistics & numerical data; D013334:Students / Q000706:statistics & numerical data; D013587:Syphilis / Q000453:epidemiology; D047568:Unsafe Sex / Q000706:statistics & numerical data; D055815:Young Adult