This study analyzes the spatial dynamics of drug users’ recruitment chains in the context of a respondent-driven sampling (RDS) study in the city of Recife, Brazil. The purpose is to understand the geographic bottlenecks, influenced by social geography, which have been a major challenge for RDS-based studies. Temporo-spatial analysis was used. Sequential maps depicted the dynamics of the recruiting process, considering neighborhood of residence and/or places of drug use. Poisson regression was fitted to model the recruiting rate by neighborhood of residence and/or places of drug use, and the different neighborhoods’ demographics. The distance between neighborhood of residence and/or places of drug use and the assessment center was negatively associated with recruitment. There was a positive association between the proportion of the population living in informal settings and the recruiting rate per neighborhood of residence and/or places of drug use. Recruitment chains depend on the social geography and demographics of the population. Studies should incorporate seeds from as many neighborhoods as possible, and more than one assessment center should be utilized.
1. Heckathorn DD. Respondent driven sampling: a new approach to the study of hidden population. Social Problems. 1997;44(2):174-199.
2. Heckathorn DD. Respondent-driven sampling II: deriving valid population estimates from chain-referral samples of hidden populations. Social Problems. 2002;49(1):11-34.
3. Gile KJ, Beaudry IS, Handcock MS, Ott MQ. Methods for inference from respondent-driven sampling data. Annual Review of Statistics and Its Application. 2018;5(1):65-93.
4. Johnston LG, Hakim AJ, Dittrich S, Burnett J, Kim E, White RG. A systematic review of published respondent-driven sampling surveys collecting behavioral and biologic data. AIDS and Behavior. 2016;20(8):1754-1776.
5. Montealegre JR, Johnston LG, Murrill C, Monterroso E. Respondent driven sampling for HIV biological and behavioral surveillance in Latin America and the Caribbean. AIDS and Behavior . 2013;17(7):2313-2340.
6. Khabbazian M, Hanlon B, Russek Z, Rohe K. Novel Sampling Design for Respondent-driven Sampling. Electronic Journal of Statistics. 2017;11(2):4769-4812.
7. Salganik MJ. Commentary: Respondent-driven Sampling. Epidemiology. 2012;23(1):148-150.
8. Toledo L, Codeço CT, Bertoni N, Albuquerque E, Malta M, Bastos FI, et al. Putting respondent-driven sampling on the map: insights from Rio de Janeiro, Brazil. Journal of Acquired Immune Deficiency Syndromes. 2011;57(Suppl 3):S136-S143.
9. Bastos FI. Structural violence in the context of drug policy and initiatives aiming to reduce drug-related harm in contemporary Brazil: a review. Substance Use & Misuse. 2012;47(13-14):1603-1610.
10. McCreesh N, Johnston LG, Copas A, Sonnenberg P, Seeley J, Hayes RJ, et al. Evaluation of the role of location and distance in recruitment in respondent-driven sampling. International Journal of Health Geographics. 2011;10(1):56.
11. Young AM, Rudolph AE, Quillen D, Havens JR. Spatial, temporal and relational patterns in respondent-driven sampling: evidence from a social network study of rural drug users. Journal of Epidemiology and Community Health. 2014;68(8):792-798.
12. Montealegre JR, Risser JM, Selwyn BJ, McCurdy SA, Sabin K. Effectiveness of Respondent Driven Sampling to Recruit Undocumented Central American Immigrant Women in Houston, Texas for an HIV Behavioral Survey. AIDS and Behavior . 2013;17(2):719-727.
13. Waiselfisz JJ. Mapa da Violência 2016: Homicídios por Armas de Fogo no Brasil. Brasilia: FLACSO Brasil; 2016.
14. Bastos F. Taxas de infecção de HIV e sífilis e inventário de conhecimento, atitudes e práticas de risco relacionadas às infecções sexualmente transmissíveis entre usuários de drogas em 10 municípios brasileiros. Brasília: Ministério da Saúde, Departamento de Vigilância, Prevenção e Controle das IST, do HIV/Aids e das Hepatites Virais; 2009.
15. Santos NTV. Vulnerabilidade e prevalência de HIV e sífilis em usuários de drogas no Recife: resultados de um estudo respondent-driven sampling. [Tese de Douturado]. Recife: Centro de Pesquisas Aggeu Magalhães, Fundação Oswaldo Cruz; 2013.
16. Instituto Brasileiro de Geografia e Estatística. Cidades [Internet]. 2016 [citado 23 mar 2018]. Disponible en: https://tinyurl.com/y59us2kz
17. Organización Panamericana de la Salud. Encuesta de comportamiento en CODAR: Herramientas básicas Diseño del estudio adaptación del cuestionario e indicadores. Washington DC: OPS; 2008.
18. Instituto Brasileiro de Geografia e Estatística. Downloads [Internet]. 2016 [citado 23 mar 2018]. Disponible en: https://tinyurl.com/ya74669m
19. Instituto Brasileiro de Geografia e Estatística. Censo Demográfico 2010: Aglomerados Subnormais - Primeiros Resultados. Rio de Janeiro: IBGE; 2011.
20. Associação Brasileira de Empresas de Pesquisa. Critério Brasil [Internet]. [citado 23 mar 2018]. Disponible en: http://www.abep.org/criterio-brasil
21. McCullagh P, Nelder JA. Generalized Linear Models. 2nd ed. New York: Chapman & Hall, CRC; 1989.
22. Csardi G, Nepusz T. The igraph software package for complex network research. InterJournal Complex Systems. 2006;1695.
23. Bivand R, Lewin-Koh N, Pebesma E, Archer E, Baddeley A, Bibiko H-J, et al. Maptools: Tools for handling spatial objects [Internet]. 2014 [citado 23 mar 2018]. https://tinyurl.com/y36pw4xa
24. McCreesh N, Frost SDW, Seeley J, Katongole J, Tarsh MN, Ndunguse R, et al. Evaluation of respondent-driven sampling. Epidemiology. 2012;23(1):138-147.
25. Frere-Smith T, Luthra R, Platt L. Sampling recently arrived immigrants in the UK: Exploring the effectiveness of respondent driven sampling. Colchester: University of Essex, Institute for Social and Economic Research; 2014. ISER Working Paper Series, No. 2014-25.
26. Bastos FI, Bastos LS, Coutinho C, Toledo L, Mota JC, Velasco-de-Castro CA, et al. HIV, HCV, HBV and syphilis among transgender women from Brazil: Assessing different methods to adjust infection rates of a hard-to-reach, sparse population. Medicine (Baltimore). 2018;97(Suppl 1):S16-S24.
27. Rudolph AE, Gaines TL, Lozada R, Vera A, Brouwer KC. Evaluating outcome-correlated recruitment and geographic recruitment bias in a respondent-driven sample of people who inject drugs in Tijuana, Mexico. AIDS and Behavior . 2014;18(12):2325-2337.
28. Rossi D, Zunino Singh D, Pawlowicz MP, Touzé G, Bolyard M, Mateu-Gelabert P, et al. Changes in time-use and drug use by young adults in poor neighbourhoods of Greater Buenos Aires, Argentina, after the political transitions of 2001-2002: Results of a survey. Harm Reduction Journal. 2011;8(1):2.
29. Rhodes T, Ball A, Stimson G V, Kobyshcha Y, Fitch C, Pokrovsky V, et al. HIV infection associated with drug injecting in the newly independent states, eastern Europe: the social and economic context of epidemics. Addiction. 1999;94(9):1323-1336.
30. Galea S, Rudenstine S. Challenges in understanding disparities in drug use and its consequences. Journal of Urban Health. 2005;82(Suppl 3):S5-S12.
31. Velez C, Barros R, Ferreira F. Inequality and economic development in Brazil. Washington DC: World Bank Publications; 2014.
32. Boiteux L. Drugs and prisons: The repression of drugs and the increase of the Brazilian penitentiary population. In: Metaal P, Youngers C, (eds.). Systems overload: Drug laws and prisons in Latin America. Amsterdam: Transnational Institute, the Washington Office on Latin America; 2011.
33. Soares L. Tudo ou nada. Rio de Janeiro: Nova Fronteira; 2012.