title: Impact of statistical adjustment for frequency of venue attendance in a venue-based survey of men who have sex with men.
abstract: Venue sampling is a common sampling method for populations of men who have sex with men (MSM); however, men who visit venues frequently are more likely to be recruited. While statistical adjustment methods are recommended, these have received scant attention in the literature. We developed a novel approach to adjust for frequency of venue attendance (FVA) and assess the impact of associated bias in the ManCount Study, a venue-based survey of MSM conducted in Vancouver, British Columbia, Canada, in 2008-2009 to measure the prevalence of human immunodeficiency virus and other infections and associated behaviors. Sampling weights were determined from an abbreviated list of questions on venue attendance and were used to adjust estimates of prevalence for health and behavioral indicators using a Bayesian, model-based approach. We found little effect of FVA adjustment on biological or sexual behavior indicators (primary outcomes); however, adjustment for FVA did result in differences in the prevalence of demographic indicators, testing behaviors, and a small number of additional variables. While these findings are reassuring and lend credence to unadjusted prevalence estimates from this venue-based survey, adjustment for FVA did shed important insights on MSM subpopulations that were not well represented in the sample.
authors: Department of Statistics, Faculty of Science, University of British Columbia, 3182 Earth Sciences Building, 2207 Main Mall, Vancouver, BC V6T 1Z4, Canada. gustaf@stat.ubc.ca
authors: Paul
authors: P
authors: Gustafson
authors: Mark
authors: M
authors: Gilbert
authors: Michelle
authors: M
authors: Xia
authors: Warren
authors: W
authors: Michelow
authors: Wayne
authors: W
authors: Robert
authors: Terry
authors: T
authors: Trussler
authors: Marissa
authors: M
authors: McGuire
authors: Dana
authors: D
authors: Paquette
authors: David M
authors: DM
authors: Moore
authors: Reka
authors: R
authors: Gustafson
mesh_terms: D000328:Adult; D001499:Bayes Theorem; D002170:Canada; D018451:Homosexuality, Male; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011159:Population Surveillance; D015983:Selection Bias
keywords: HCV; HIV; data collection; models, statistical; population surveillance; prevalence; selection bias; sexual behavior