title: Predictors of retention in an online follow-up study of men who have sex with men.
abstract: BACKGROUND
  In the past 10 years, the Internet has emerged as a venue for men who have sex with men (MSM) to meet sex partners. Because online sex seeking has increased among MSM, Internet-based human immunodeficiency virus (HIV) prevention interventions are of interest. However, few online studies to date have demonstrated an ability to retain study participants, specifically MSM of color, in longitudinal online studies.
  
  
  OBJECTIVE
  The current analysis examines data from a 3-month online prospective study of MSM to determine the association of race and incentive level with two retention outcomes: (1) agreeing to participate in a follow-up survey and providing an email address and (2) linking into the follow-up survey at the follow-up time point.
  
  
  METHODS
  Internet-using MSM were recruited through banner advertisements on MySpace.com. White, black, and Hispanic participants from 18 to 35 years of age were randomized to an offer of enrollment in an online follow-up survey at four levels of incentive (US $0, US $5, US $10, and US $20). Multivariable logistic regression models were used to estimate the odds of the two outcome measures of interest controlling for additional independent factors of interest.
  
  
  RESULTS
  Of eligible participants, 92% (2405/2607) agreed to participate in the follow-up survey and provided an email address. Hispanic men had decreased odds (adjusted odds ratio [OR] = 0.66, 95% confidence interval [CI] 0.47-0.92) of agreeing to participate in the follow-up survey compared with white men. Men reporting unprotected anal intercourse with a male sex partner in the past 12 months had increased odds of agreeing to participate in the follow-up survey (adjusted OR = 1.42, 95% CI 1.05-1.93). Of the participants who provided an email address, 22% (539/2405) linked into the follow-up survey at the 3-month follow-up time point. The odds of linking into the follow-up survey for black men were approximately half the odds for white men (adjusted OR = 0.47, 95% CI 0.35-0.63). Participants who were offered an incentive had increased odds of linking into the follow-up survey (adjusted OR = 1.29, 95% CI 1.02-1.62). Email addresses provided by participants that were used for online financial management and email accounts that were checked daily were associated with increased odds of linking into the follow-up survey (adjusted OR = 1.97, 95% CI 1.54-2.52; adjusted OR = 1.51, 95% CI 1.22-1.87, respectively).
  
  
  CONCLUSIONS
  This analysis identified factors that predicted retention in an online, prospective study of MSM. Hispanic and black study participants were less likely to be retained in the study compared with white study participants. Because these men bear the greatest burden of HIV incidence among MSM in the United States, it is critical that new research methods be developed to increase retention of these groups in online research studies.
authors: Rollins School of Public Health, Department of Epidemiology, Emory University, Atlanta, GA, USA.
authors: Christine M
authors: CM
authors: Khosropour
authors: Patrick S
authors: PS
authors: Sullivan
mesh_terms: D000328:Adult; D016001:Confidence Intervals; D005006:Ethnicity / Q000706:statistics & numerical data*; D005500:Follow-Up Studies; D015658:HIV Infections / Q000517:prevention & control* / Q000635:transmission; D006293:Health Promotion / Q000458:organization & administration*; D018451:Homosexuality, Male / Q000523:psychology / Q000706:statistics & numerical data*; D006801:Humans; D020407:Internet / Q000458:organization & administration*; D008297:Male; D015999:Multivariate Analysis; D016017:Odds Ratio; D011446:Prospective Studies; D012309:Risk-Taking; D012736:Sex Education / Q000458:organization & administration*; D012747:Sexual Partners / Q000145:classification* / Q000523:psychology; D014481:United States; D055815:Young Adult