title: [Loss to follow-up and associated factors in a cohort study among men who have sex with men].
abstract: OBJECTIVE
  To explore the associated factors on loss to follow-up among men who have sex with men (MSM) in a prospective cohort study.
  
  
  METHODS
  We recruited eligible HIV-negative MSM at baseline in eight cities from June to October 2009. Interviewer-administrated questionnaire and blood testings for HIV, syphilis and human simplex virus type 2, were accomplished upon enrollment, 6-month and 12-month follow-up visits in the program. Loss to follow-up was recorded at each visit in this cohort. Univariate and multivariate statistical analysis were conducted to examine the associated factors on loss to follow-up.
  
  
  RESULTS
  A total of 3196 eligible MSM were enrolled at the baseline study. During one year of follow-up, 894 (28.0%) of them dropped out thoroughly while 2302 (72.1%) showed up at least on one visit. Factors as MSM who were at age 25 or younger, resided locally less than 1 year, being unemployed, self-recognized as heterosexuality or bisexuality, never taking HIV testing in the past year, having had sex with women in the past 6 months etc., were more likely to withdraw from the follow-up visits. Conclusion Age, length of residency, sex orientation and history of HIV testing were associated with the loss of follow-up among MSM cohort in our study. These factors should be considered in this kind of study design in the future.
authors.affiliation: National Center for AIDS/STD Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China.
authors.forename: Chu
authors.initials: C
authors.lastname: Zhou
authors.affiliation: National Center for AIDS/STD Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Xu
authors.affiliation: National Center for AIDS/STD Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Dou
authors.affiliation: China-US Cooperation-Global AIDS Program.
authors.forename: Guo-Dong
authors.initials: GD
authors.lastname: Mi
authors.affiliation: National Center for AIDS/STD Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China.
authors.forename: Yu-Hua
authors.initials: YH
authors.lastname: Ruan
authors.affiliation: Guizhou Provincial Center for Disease Control and Prevention.
authors.forename: Li-Mei
authors.initials: LM
authors.lastname: Shen
authors.affiliation: Yunnan Provincial Center for Disease Control and Prevention.
authors.forename: Xiang-Dong
authors.initials: XD
authors.lastname: Min
authors.affiliation: Guangxi Zhuang Autonomous Region Center for Disease Control and Prevention.
authors.forename: Guang-Hua
authors.initials: GH
authors.lastname: Lan
authors.affiliation: Xinjiang Uygur Autonomous Region Center for Disease Control and Prevention.
authors.forename: Fan
authors.initials: F
authors.lastname: Li
authors.affiliation: Chengdu Center for Disease Control and Prevention.
authors.forename: Tian
authors.initials: T
authors.lastname: Li
authors.affiliation: Shanghai Municipal Center for Disease Control and Prevention.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Ning
authors.affiliation: Chongqing Municipal Center for Disease Control and Prevention.
authors.forename: Guo-Hui
authors.initials: GH
authors.lastname: Wu
authors.affiliation: National Center for AIDS/STD Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China.
authors.forename: Zun-You
authors.initials: ZY
authors.lastname: Wu
mesh_terms: D000328:Adult; D001727:Bisexuality; D015331:Cohort Studies; D005500:Follow-Up Studies; D018451:Homosexuality, Male; D006801:Humans; D008297:Male; D011446:Prospective Studies; D012725:Sexual Behavior