Loss to follow-up and bias assessment among a cohort of Thai men who have sex with men in Bangkok, Thailand.
Minimising loss to follow-up is essential to obtain unbiased results. This study aimed to assess factors associated with loss to follow-up and effects on biasing exposure-outcome associations in a cohort of men who have sex with men in Bangkok. We enrolled sexually-active Thai men who have sex with men, at least 18 years old, in a study with four-monthly follow-up visits. At each visit, men answered HIV risk behaviour questions using audio computer-assisted self-interview. Logistic regression was used to evaluate factors associated with loss to follow-up and bias between exposures and prevalent HIV infection were estimated using adjusted relative odds ratios. From 2006 to 2010, we enrolled 1744 men who have sex with men; as of April, 2014, 1256 (72%) had completed at least the month-36 visit; loss to follow-up was 9.6%. Factors independently associated with loss to follow-up were age (18-21 years), education (primary level or less, secondary or vocational education), living outside Bangkok and vicinity, sexual orientation (bisexual, heterosexual), previous HIV testing, HIV infection, and behaviour in the past 4 months (recreational drug use, reporting group sex). An effect of loss to follow-up on factors of prevalent HIV infection was found by sexual orientation (transgender) and unprotected anal intercourse (receptive/insertive). These findings highlight the need to strengthen post-HIV test counselling. Directed counselling for HIV care should be given to young men who have sex with men and recreational drug users.
['Pattanasin|Sarika|S|', 'Wimonsate|Wipas|W|', 'Chonwattana|Wannee|W|', 'Tongtoyai|Jaray|J|', 'Chaikummao|Supaporn|S|', 'Sriporn|Anuwat|A|', 'Sukwicha|Wichuda|W|', 'Mock|Philip A|PA|', 'Holtz|Timothy H|TH|']
D000293:Adolescent D000328:Adult D015982:Bias D015331:Cohort Studies D005500:Follow-Up Studies D015658:HIV Infections D018451:Homosexuality, Male D006801:Humans D016015:Logistic Models D059012:Lost to Follow-Up D008297:Male D016017:Odds Ratio D015995:Prevalence D012309:Risk-Taking D012747:Sexual Partners D013785:Thailand D047568:Unsafe Sex D055815:Young Adult
loss to follow-up men men who have sex with men HIV AIDS Asia Epidemiology MSM high-risk behaviour homosexual prospective studies