Abstract
To assess the reproducibility of respondent-driven sampling (RDS) in obtaining comparable samples across two survey rounds, we conducted integrated bio-behavioral surveillance surveys (IBBSS) using RDS in 2007 and 2011 among men who have sex with men (MSM) on Unguja island in Zanzibar. Differences in the two rounds were assessed by comparing RDS-adjusted population estimates, stratified estimates, and bottleneck plots. Participants in the 2011 survey round were younger (31.4 vs. 9.9% under 19 years old, p < 0.001), more likely to have tested for HIV in the last year (53.7 vs. 10.6%, p < 0.001), and less likely to have injected drugs in the last 3 months (1.0 vs. 23.2%, p < 0.001) compared to participants in the 2007 round. HIV prevalence was 12.3% in 2007 compared to 2.6% in 2011 (p < 0.001). The difference in HIV prevalence persisted after stratifying and adjusting for known differences in the two surveys rounds. Bottleneck plots suggest that recruitment chains were “trapped” in the social networks of MSM who injected drugs to a greater extent in 2007 than in 2011. We conclude that the two rounds of RDS sampled different subsets of the MSM population on Unguja, particularly with respect to inclusion of MSM within the social networks of people who inject drugs. Findings underscore the need to evaluate the reproducibility of RDS in repeated rounds of IBBSS and to develop new sampling methods for key populations at high risk for HIV in order to track the epidemic, develop evidence-based prevention and care programs, and assess their impact.
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References
Heckathorn DD. Extensions of respondent driven sampling: analyzing continuous variables and controlling for differential recruitment. Sociol Methodol. 2007;37(1):151–207.
Ramirez-Valles J, Heckathorn DD, Vázquez R, Diaz RM, Campbell RT. From networks to populations: the development and application of respondent-driven sampling among IDUs and Latino gay men. AIDS Behav. 2005;9(4):387–402.
MacKellar DA, Gallagher KM, Finlayson T, Sanchez T, Lansky A, Sullivan PS. Surveillance of HIV risk and prevention behaviors of men who have sex with men–a national application of venue-based, time-space sampling. Public Health Rep. 2007;122(Suppl 1):39–47 Epub 2007/03/16.
Zanzibar AIDS Control Programme. HIV ANC Surveillance Report. Unpublished: Zanzibar AIDS Control Programme, 2010
Kajubi P, Kamya MR, Raymond HF, Chen S, Rutherford GW, Mandel JS, et al. Gay and bisexual men in Kampala, Uganda. AIDS Behav. 2008;12(3):492–504.
Lane T, Raymond HF, Dladla S, Rasethe J, Struthers H, McFarland W, et al. High HIV prevalence among men who have sex with men in Soweto, South Africa: results from the Soweto men’s study. AIDS Behav. 2011;15(3):626–34.
Dahoma M, Johnston LG, Holman A, Miller LA, Mussa M, Othman A, et al. HIV and related risk behavior among men who have sex with men in Zanzibar, Tanzania: results of a behavioral surveillance survey. AIDS Behav. 2011;15(1):186–92.
Liao M, Nie X, Pan R, Wang C, Ruan S, Zhang C, et al. Consistently low prevalence of syphilis among female sex workers in Jinan, China: findings from two consecutive respondent driven sampling surveys. PLoS ONE. 2012;7(4):e34085.
Ruan S, Yang H, Zhu Y, Wang M, Ma Y, Zhao J, et al. Rising HIV prevalence among married and unmarried among men who have sex with men: Jinan, China. AIDS Behav. 2009;13(4):671–6.
Ma X, Zhang Q, He X, Sun W, Yue H, Chen S, et al. Trends in prevalence of HIV, syphilis, hepatitis C, hepatitis B, and sexual risk behavior among men who have sex with men: results of 3 consecutive respondent-driven sampling surveys in Beijing, 2004 through 2006. J Acquir Immune Defic Syndr. 2007;45(5):581–7.
Townsend L, Johnston LG, Flisher AJ, Mathews C, Zembe Y. Effectiveness of respondent-driven sampling to recruit high risk heterosexual men who have multiple female sexual partners: differences in HIV prevalence and sexual risk behaviours measured at two time points. AIDS Behav. 2010;14(6):1330–9.
Burt RD, Thiede H. Evaluating consistency in repeat surveys of injection drug users recruited by respondent-driven sampling in the Seattle area: results from the NHBS-IDU1 and NHBS-IDU2 surveys. Ann Epidemiol. 2012;22(5):354–63.
Abdul-Quader AS, Heckathorn DD, McKnight C, Bramson H, Nemeth C, Sabin K, et al. Effectiveness of respondent-driven sampling for recruiting drug users in New York City: findings from a pilot study. J Urban Health. 2006;83(3):459–76 Epub 2006/06/02.
Malekinejad M, Johnston LG, Kendall C, Kerr LR, Rifkin MR, Rutherford GW. Using respondent-driven sampling methodology for HIV biological and behavioral surveillance in international settings: a systematic review. AIDS Behav. 2008;12(4 Suppl):S105–30 Epub 2008/06/19.
MOHSW. Guidelines for HIV testing and counselling in clinical settings. In: Programme NAC, editor. United Republic of Tanzania: Ministry of Health & Social Welfare; 2008.
Gile KJ, Johnston LG, Salganik MJ. Diagnostics for respondent-driven sampling. J R Stat Soc Ser A Stat Soc. 2015;178(1):241–69.
Sabin KM, Johnston LG. Epidemiological challenges to the assessment of HIV burdens among key populations: respondent-driven sampling, time-location sampling and demographic and health surveys. Curr Opin HIV AIDS. 2014;9(2):101–6 Epub 2014/01/28.
Matiko E, Khatib A, Khalid F, Welty S, Said C, Ali A, et al. HIV prevalence and risk behaviors among people who inject drugs in two serial cross-sectional respondent-driven sampling surveys, Zanzibar 2007 and 2012. AIDS Behav. 2014;19(1):36–45 Epub 2014/11/17.
Tanzania URo. Tanzania HIV/AIDS Indicator Survey 2011–2012. 2012.
Gile KJ, Handcock MS. Respondent-driven sampling: an assessment of current methodology. Sociol Methodol. 2010;40(1):285–327.
Handcock MS, Gile KJ, Mar CM. Estimating hidden population size using respondent-driven sampling data. Electron J Stat. 2014;8(1):1491–521.
Salganik MJ. Commentary: respondent-driven sampling in the real world. Epidemiol Camb Mass. 2012;23(1):148–50.
Goel S, Salganik MJ. Assessing respondent-driven sampling. Proc Natl Acad Sci USA. 2010;107(15):6743–7.
Johnston LG, Chen YH, Silva-Santisteban A, Raymond HF. An empirical examniation of respondent driven sampling design effects among HIV risk groups from studies conducted around the world. AIDS Behav. 2013;17:2202–10.
Acknowledgements
We thank the numerous members of the research design and data collection team as well as the men who participated in this study.
Funding
This research was supported by the President’s Emergency Plan for AIDS Relief (PEPFAR) through the Centers for Disease Control and Prevention (CDC), cooperative agreement 5UGPS002039-02, and Global Fund Round 6 for HIV/AIDS.
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The authors have no conflicts of interest.
Research Involving in Human Participants
The research did involve human subjects in Zanzibar.
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The research was reviewed and cleared by the Zanzibar Ethical Review Board (ZAMREC), CDC ADS Non-Research Determination and UCSF’s Committee on Human Research Protection.
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All participants were consented using an approved informed consent form.
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The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the CDC or Global Fund.
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Khatib, A., Haji, S., Khamis, M. et al. Reproducibility of Respondent-Driven Sampling (RDS) in Repeat Surveys of Men Who have Sex with Men, Unguja, Zanzibar. AIDS Behav 21, 2180–2187 (2017). https://doi.org/10.1007/s10461-016-1632-2
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DOI: https://doi.org/10.1007/s10461-016-1632-2