Respondent-driven Sampling Methodology Research Articles

Use of antibiotics among small-scale cattle farmers in rural areas in Queretaro, Mexico

The inappropriate use of antibiotics in the livestock sector has been described as one of the causes of the emergence of antimicrobial resistance. Information on antibiotic use in small-scale farms is limited. Our objective was to identify patterns of antibiotic use in small-scale cattle farms in Queretaro, Mexico. Cross-sectional study with 50 small-scale cattle farmers from rural areas surveyed in the municipality of Tequisquiapan, Queretaro between May–October 2022. Convenience sampling, non-probabilistic, small-scale cattle farms were selected using respondent-driven sampling methodology. A face-to-face survey was applied, structured in five sections: i) small-scale cattle farmers´ profile, ii) characteristics of small-scale cattle farms, iii) antibiotic use, iv) antibiotic prescription, and v) inventory of stored antibiotics vials. The data collected were processed and analyzed. Ninety-two percent of the small-scale cattle farmers were male, with an age range of 23 to 88 years (median 58.5, IQR 49–64.5). Seventy-four percent of the small-scale cattle farmers had a basic level of schooling. The animal census consisted of 968 animals. A total of 142 stored antibacterial products from nine antibiotic classes were recorded: 34.5 % were penicillin, 19 % oxytetracycline, 13.4 % gentamicin, 9.8 % florfenicol, and 8.4 %enrofloxacin. About 50 % of the stored antibiotics have a "watch" classification in the WHO AWaRe tool. Seventy-eight percent of small-scale cattle farmers throw empty antibiotic vials in the trash. Our study showed that small-scale cattle farmers had an important use of third generation cephalosporins, tetracyclines, and fluoroquinolones; antibiotics considered “watch” by the WHO.

Prevalence and correlates of hazardous alcohol drinking and drug use among female sex workers and men who have sex with men in Mozambique

BackgroundHazardous drinking and drug consumption are associated with an increased risk of HIV due to the complex interplay of factors influencing decision-making capability, stigma and social marginalization. In this study, we explore the patterns of hazardous alcohol and drug use and correlates of risk factors among female sex workers (FSW) and men who as sex with men (MSM) in Mozambique.MethodsWe conducted a secondary data analysis of bio-behavioral surveys (BBS) among FSW and MSM using a respondent-driven sampling methodology conducted in five main urban areas of Mozambique from 2019 to 20. The survey included a standardized questionnaire, where hazardous drinking was assessed (using AUDIT-C scores ≥ 4 for men, ≥ 3 for women) and drug use in the last year (FSW). Chi-squared test was used to analyze the association between socio-demographic and behavioral variables, and multivariate logistic regression measured the impact of the associated factors.ResultsThe prevalence of hazardous alcohol drinking was 47.1% (95% CI:44.8–49.5) for FSW and 46.5 (95% CI: 44.0–49.0) for MSM. Current drug use was reported in 13.3% of FSW. FSW engaging in hazardous alcohol drinking reported more sexual partners in the last month than those no reporting hazardous alcohol use (55.3% vs. 47,1%, p < 0.001), higher rates of self-reported STIs in the last year (62,5% vs. 48,2%, p < 0.001), physical (53.5% vs. 46.7%, p < 0.0001) and sexual violence (54.7% vs. 44.2%, p < 0.001), and HIV prevalence (55.2% vs. 44.2 p < 0.001). Among MSM with hazardous alcohol drinking, there was a higher prevalence of self-reported STIs (52.8% vs. 45.4%, p < 0.001), experiences of sexual violence (18.0% vs. 8.3%, p < 0.001), and HIV prevalence (53.0% vs. 46.3%, p < 0.001). In addition, FSW who reported illicit drug use were more likely to self-reported HIV own risk (14.2% vs. 9.7%), early start sexual activity (15.4% vs. 5.3%), self-reported STIs (17.9% vs. 10.2%), and experiences of both physical (17.4% vs. 7.0%) and sexual violence (18.6% vs. 8.9%).ConclusionThere is an immediate need for the introduction and integration of comprehensive substance use harm mitigation and mental health interventions into HIV prevention programs, particularly those targeting key populations in Mozambique.

Online and Offline Sexual Exploitation of Boys, Young Men, and Trans/Third Gender Youth and Adults in Northern Thailand

ABSTRACT Globally, anti-trafficking prevention organizations and law enforcement have struggled to keep up with the constantly changing online spaces used for sex trade and trafficking. The current study aimed to understand the current state of online commercial sexual exploitation of boys, young men, and trans/third gender children and adults in Thailand. Using a respondent-driven sampling methodology, data were collected from 94 individuals assigned male at birth, ranging in age from 16 to 39 years old regarding 1) Demographics, 2) Entrance into Sex Trade, 3) Sex Trade & Exploitation in Person, 4) Online Sex Trade & Exploitation, 5) Physical and Emotional Safety, and 6) Accessing Support Services. Results found that the use of the internet for child sexual exploitation and sex trade is pervasive, with the majority of respondents noting participation in both in-person and online engagement with customers. Physical and sexual violence were frequently reported among respondents. Furthermore, gender norms and expectations present unique vulnerabilities for cisgender males and trans/third gender people from accessing and receiving support and services. The results of this study inform comprehensive recommendations for service providers, policymakers, funders, and researchers, and work toward the UN Sustainable Development Goal of promoting a just, peaceful, and inclusive society.

Hepatitis B Prevalence among Men Who Have Sex with Men in Brazil.

Hepatitis B virus (HBV) is a global public health problem and requires specific prevention actions, particularly focusing on the key populations, such as men who have sex with men (MSM). We aimed at assessing the prevalence of HBV infection, among MSM, in a multicity study in Brazil. In 2016, we conducted a survey using a respondent-driven sampling methodology in 12 Brazilian cities. Rapid tests (RT) were performed on 3178 samples from those MSM. Positive results were tested for HBV DNA and sequenced. If negative for HBV DNA, samples were tested for serological markers. The prevalence rate of HBV exposure and clearance was 10.1% (95% CI: 8.1-12.6), and 1.1% (95%; CI: 0.6-2.1) were confirmed to be HBsAg-positive. Of those samples tested for anti-HBs (n = 1033), only 74.4% presented a serological profile analogous to that elicited by hepatitis B vaccination. Among HBsAg-positive samples (n = 29), 72.4% were HBV DNA-positive, and from these, 18 were sequenced. HBV genotypes A, F, and G were found in 55.5%, 38.9%, and 5.6%, respectively. This study indicates high prevalence rates of MSM HBV exposure and a low positivity index for the serological marker of HBV vaccine immunity. These findings may contribute to the discussion of strategies to prevent hepatitis B and reinforce the importance of promoting HBV vaccination in this key population.

Factors associated with symptoms of major depression disorder among transgender women in Northeast Brazil.

Transgender women (TGW) are one of the most vulnerable groups, including higher prevalence of HIV and mental health disorders, such as anxiety and depression than in the general population. Major Depression Disorder (MDD) is one of the most important mental health conditions due to an increasing trend in prevalence in the general population. This study aims at describing the prevalence of symptoms of MDD (SMDD) and associated factors among TGW in capitals of three States in Northeast Brazil. TGW n = (864) were selected from the cities of Salvador (n = 166), Recife (n = 350), and Fortaleza (n = 348) using Respondent Driven Sampling methodology. Symptoms of MDD were defined according to the Patient Health Questionnaire-9 scale. Multinomial logistic regression was used to compare those with mild/moderate or moderately severe/severe symptoms of depression with those with no depression, respectively, using complex sample design. Weighted Odds Ratio with 95% confidence interval were estimated. 51.1% of the sample was classified as mild/moderate and 18.9% as moderately severe/severe SMDD. Mild/moderate SMDD was associated with a history of sexual violence (OR = 2.06, 95%CI: 1.15-3.68), history of physical violence (OR = 2.09, 95%CI: 1.20-3.67),) and poor self-rated quality of life (OR = 2.14, 95%CI: 1.31-3.49).). Moderately severe/severe SMDD was associated with history of sexual violence (OR = 3.02, 95%CI: 1.17-7.77), history of physical violence (OR = 4.34, 95% CI:1.88-6.96), poor self-rated quality of life (OR = 3.32, 95%CI:1.804-6.12), lack of current social support (OR = 2.53, 95%IC: 1.31-4.88) and lack of family support in childhood (OR = 2.17, 95%IC 1.16-4.05)). Our findings strengthens the evidence of a higher prevalence of SMDD among TGW as compared to the general population. Public health policies and actions that target social determinants of risk and protection for MDD among TGW must be urgently implemented.

Challenges of virtual RDS for recruitment of sexual minority women for a behavioral health study.

Respondent driven sampling (RDS) is an approach commonly used to recruit nonprobability samples of rare and hard-to-find populations. The purpose of this study was to explore the utility of phone and web-based RDS methodology to sample sexual minority women (SMW) for participation in a telephone survey. Key features included 1) utilizing a national probability survey sample to select seeds; 2) web-based recruitment with emailed coupons; and 3) virtual processes for orienting, screening and scheduling potential participants for computer-assisted telephone interviews. Rather than resulting in a large diverse sample of SMW, only a small group of randomly selected women completed the survey and agreed to recruit their peers, and very few women recruited even one participant. Only seeds from the most recent of two waves of the probability study generated new SMW recruits. Three RDS attempts to recruit SMW over several years and findings from brief qualitative interviews revealed four key challenges to successful phone and web-based RDS with this population. First, population-based sampling precludes sampling based on participant characteristics that are often used in RDS. Second, methods that distance prospective participants from the research team may impede development of relationships, investment in the study, and motivation to participate. Third, recruitment for telephone surveys may be impeded by multiple burdens on seeds and recruits (e.g., survey length, understanding the study and RDS process). Finally, many seeds from a population-based sample may be needed, which is not generally feasible when working with a limited pool of potential seeds. This method may yield short recruitment chains, which would not meet key RDS assumptions for approximation of a probability sample. In conclusion, potential challenges to using RDS in studies with SMW, particularly those using virtual approaches, should be considered.

Telephone peer recruitment and interviewing during a respondent-driven sampling (RDS) survey: feasibility and field experience from the first phone-based RDS survey among men who have sex with men in C\xf4te d\u2019Ivoire

BackgroundMany respondent-driven sampling (RDS) methodologies have been employed to investigate hard-to-reach populations; however, these methodologies present some limits. We describe a minimally investigated RDS methodology in which peer recruitment and interviewing are phone-based. The feasibility of the methodology, field experiences, validity of RDS assumptions and characteristics of the sample obtained are discussed.MethodsWe conducted a phone-based RDS survey among men who have sex with men (MSM) aged 18 or above and living in Côte d’Ivoire. Eight initial MSM across Côte d’Ivoire were selected. Participants were asked to call a hotline to be registered and interviewed by phone. After the participants completed the questionnaire, they were asked to recruit a maximum of 3 MSM from their acquaintances.ResultsDuring the 9 months of the survey, 576 individuals called the hotline, and 518 MSM completed the questionnaire. The median delay between the invitation to participate and the completion of the questionnaire by peer-recruited MSM was 4 days [IQR: 1–12]. The recruitment process was not constant, with high variation in the number of people who called the hotline during the survey period.RDS chain convergence to equilibrium was reached within 6 waves for most of the selected variables. For the network size estimation assumption, participants who incorrectly estimated their network size were observed.Regarding the sample obtained, MSM were recruited from all the regions of Côte d’Ivoire with frequent interregional recruitment; 23.5% of MSM were recruited by someone who does not live in the same region. Compared to the MSM who participated in two other surveys in Côte d’Ivoire, the MSM in our sample were less likely to know about an MSM non-governmental organisation. However, MSM aged 30 years old and above and those with a low level of education were underrepresented in our sample.ConclusionWe show that phone-based RDS surveys among MSM are feasible in the context of sub-Saharan Africa. Compared to other classical RDS survey methodologies, the phone-based RDS methodology seems to reduce selection bias based on geography and proximity with the MSM community. However, similar to other methodologies, phone-based RDS fails to reach older and less-educated MSM.

“Strive harder and don't lose hope”: sexual exploitation of male youth in the sex trade in Manila

PurposeThe purpose of this research is to understand the vulnerabilities of male youth in the sex trade in Manila, Philippines. Using purposive and a modified respondent-driven sampling methodology, interviews were conducted with 51 young males working as masseurs in the Metro Manila area exploring a wide range of their experiences and vulnerabilities throughout the work including physical, sexual and emotional violence. The mixed method, mostly qualitative research is based on similar surveys conducted throughout the South and South Asia regions.Design/methodology/approachResearch on sexual exploitation of boys and men has largely focused on sexual health and prevention of HIV (Human Rights Watch Philippines, 2004). This research uniquely focuses on a broader range of vulnerabilities for males in the sex trade.FindingsQualitative discussions reveal instances of forced sex that can take a variety of forms, including physical force and/or violence or coercion involving bribes, verbal abuse or other forms of pressure to provide sexual services. Data also demonstrate stigma and discrimination outside of sex work. This study provides a qualitative assessment of the broader male-to-male sex industry within the Metro-Manila area, including escort services and both direct and indirect male sex work.Originality/valueFor observers, who consider male sexual abuse to be free of violence or discrimination, this provides evidence to the contrary and considerations for organizations that are able to provide funding to support their needs. Education of those involved in addressing the prevention of sexual exploitation should include gendered differences.

Surveying migrant populations with respondent-driven sampling. Experiences from surveys of east-west migration in Europe

ABSTRACT Respondent-driven sampling (RDS) is a methodology for sampling and analysing survey data from rare and elusive populations that has gained increasing attention in migration research in recent years. Since its introduction in 1997, it has been applied in numerous surveys in the field of epidemiology (mainly for the estimation of HIV/AIDS prevalence in high-risk populations) and increasingly in migration research. This article summarises some of the experiences of applying RDS to study migrant populations, in light of some of the key assumptions that the methodology builds on, pointing to the advantages, but also the limitations of this approach. If sample frames of reasonable quality are available or can be produced, this will normally be preferable to RDS. But if no sample frame is available, the RDS methodology does create opportunities for a more systematic approach to the study of marginalized migrant populations, where qualitative studies, and convenience samples thus far have dominated knowledge production.

HIV and other sexually transmitted infections among female sex workers in Moscow (Russia): prevalence and associated risk factors

To estimate the prevalence and factors associated with HIV and five other STIs among outdoor female sex workers (OSFW) and indoor FSW (IFSW).MethodsCross-sectional survey using respondent-driven sampling methodology. Participants answered...

Využití metody Respondent-Driven Sampling u populace lidí bez domova: základní principy, aplikace a praktická doporučení

Respondent-driven sampling (RDS) is a survey method used to create samples of populations that are hidden and hard to reach. Even though the method has been used since the 1990s in studies internationally, it has not yet been used in Czech research. The RDS methodology tends to be described presented as a statistical tool that makes it possible to produce unbiased estimates of hidden or hard-to-reach populations, and at the same as a tool with which to effectively recruit respondents from the given populations. The goal of the article is to introduce RDS methodology and its uses and to present and assess its application in a homeless survey conducted in two Czech cities - Prague (N=322) and Pilsen (N=146). We show that as long as certain preconditions are met the method proves to be fact and effective, especially with respect to the speed at which it is possible to sample the homeless population. We compare the outcome of the RDS survey with that of a survey of the homeless population in Prague (2010) and assess whether and how the outcomes of the two samples differ in certain population characteristics. Finally, we offer practical suggestions and observations on using the RDS method for sampling homeless populations.

Application of the Respondent-Driven Sampling methodology in a biological and behavioral surveillance survey among female sex workers, Brazil, 2016.

Respondent-Driven Sampling (RDS) has been used in surveys with key populations at risk of HIV infection, such as female sex workers (FSW). This article describes the application of the RDS method among FSW in 12 Brazilian cities, during a survey carried out in 2016. A biological and behavioral surveillance study carried out in 12 Brazilian cities, with a minimum sample of 350 FSW in each city. Tests were performed for HIV, syphilis, and hepatitis B and C infections. A social-behavioral questionnaire was also applied. The sample was comprised of 4,328 FSW. For data analysis, the sample was weighted according to each participant's network size (due consideration to the implications of RDS complex design and to the effects of homophilia are recommended). Although RDS methods for obtaining a statistical sample are based on strong statistical assumptions, allowing for an estimation of statistical parameters, with each new application the method has been rethought. In the analysis of whole-sample data, estimators were robust and compatible with those found in 2009. However, there were significant variations according to each city. The achieved sample size was of great relevance for assessing progress and identifying problems regarding the prevention and treatment of Sexually Transmitted Infections. New RDS studies with more time and operational resources should be envisaged. This could further network development.

Lessons Learned From the Implementation of HIV Biological-Behavioral Surveys of Key Populations in the Caribbean.

In the Caribbean region, HIV prevalence is high among key population (KP) groups, such as sex workers and men who have sex with men. However, there is a lack of high-quality, population-level data estimating HIV prevalence and population sizes of KPs. The President's Emergency Plan for AIDS Relief has funded and completed five bio-behavioral surveillance (BBS) surveys using respondent-driven sampling methodology to target KP in the English-speaking Caribbean region. We describe the experience of implementing bio-behavioral surveys in the Caribbean region and document the context, processes, successes, and challenges, and make recommendations for future survey implementation. Successes include the provision of estimates of nationally representative HIV data and KP size estimates to improve HIV programming and provision of tools for routinization of BBS. Challenges include small KP sizes, the legal context, and the cost and speed of implementation. Future bio-behavioral surveys should include well-planned formative assessments and stakeholder involvement.

Using Respondent Driven Sampling to Identify Malaria Risks and Occupational Networks among Migrant Workers in Ranong, Thailand.

BackgroundRanong Province in southern Thailand is one of the primary entry points for migrants entering Thailand from Myanmar, and borders Kawthaung Township in Myanmar where artemisinin resistance in malaria parasites has been detected. Areas of high population movement could increase the risk of spread of artemisinin resistance in this region and beyond.MethodsA respondent-driven sampling (RDS) methodology was used to compare migrant populations coming from Myanmar in urban (Site 1) vs. rural (Site 2) settings in Ranong, Thailand. The RDS methodology collected information on knowledge, attitudes, and practices for malaria, travel and occupational histories, as well as social network size and structure. Individuals enrolled were screened for malaria by microscopy, Real Time-PCR, and serology.ResultsA total of 619 participants were recruited in Ranong City and 623 participants in Kraburi, a rural sub-district. By PCR, a total of 14 (1.1%) samples were positive (2 P. falciparum in Site 1; 10 P. vivax, 1 Pf, and 1 P. malariae in Site 2). PCR analysis demonstrated an overall weighted prevalence of 0.5% (95% CI, 0–1.3%) in the urban site and 1.0% (95% CI, 0.5–1.7%) in the rural site for all parasite species. PCR positivity did not correlate with serological positivity; however, as expected there was a strong association between antibody prevalence and both age and exposure. Access to long-lasting insecticidal treated nets remains low despite relatively high reported traditional net use among these populations.ConclusionsThe low malaria prevalence, relatively smaller networks among migrants in rural settings, and limited frequency of travel to and from other areas of malaria transmission in Myanmar, suggest that the risk for the spread of artemisinin resistance from this area may be limited in these networks currently but may have implications for regional malaria elimination efforts.

Respondent driven sampling of wheelchair users: A lack of traction?

Internationally, wheelchair users are an emerging demographic phenomenon, due to their increased prevalence and rapidly increasing life-span. While having significant healthcare implications, basic robust epidemiological information about wheelchair users is often lacking due, in part, to this population's 'hidden' nature. Increasingly popular in epidemiological research, Respondent Driven Sampling (RDS) provides a mechanism for generating unbiased population-based estimates for hard-to-reach populations, overcoming biases inherent within other sampling methods. This paper reports the first published study to employ RDS amongst wheelchair users. Between October 2015 and January 2016, a short, successfully piloted, internet-based national survey was initiated. Twenty seeds from diverse organisations were invited to complete the survey then circulate it to peers within their networks following a well-defined protocol. A predetermined reminder protocol was triggered when seeds or their peers failed to respond. All participants were entered into a draw for an iPad. Overall, 19 people participated (nine women); 12 initial seeds, followed by seven second-wave participants arising from four seeds . Completion time for the survey ranged between 7 and 36 minutes. Despite repeated reminders, no further people were recruited. While New Zealand wheelchair user numbers are unknown, an estimated 14% of people have physical impairments that limited mobility. The 19 respondents generated from adopting the RDS methodology here thus represents a negligible fraction of wheelchair users in New Zealand, and an insufficient number to ensure equilibrium required for unbiased analyses. While successful in other hard-to-reach populations, applying RDS methodology to wheelchair users requires further consideration. Formative research exploring areas of network characteristics, acceptability of RDS, appropriate incentive options, and seed selection amongst wheelchair users is needed.

Respondent driven sampling of wheelchair users: A lack of traction?

Internationally wheelchair users are an emerging demographic phenomenon due to their rapidly increasing life-span coupled with accelerated general population ageing. While having significant healthcare and social implications, basic robust epidemiological information of wheelchair users is often lacking due in part to this population's "hidden" nature. Increasingly popular in epidemiological research, Respondent Driven Sampling (RDS) provides a mechanism for generating unbiased population-based estimates for hard-to-reach populations, overcoming biases inherent within other sampling methods. This paper reports the first published study to employ RDS amongst wheelchair users. Between October 2015 and January 2016, a short, successfully piloted, internet-based national survey was initiated. Twenty seeds from diverse organisations were invited to complete the survey then circulate it to peers within their networks following a well-defined protocol. A predetermined reminder protocol was triggered when seeds or their peers failed to respond. All participants were entered into a draw for an iPad. Overall, 19 people participated (9 women); 12 initial seeds, followed by seven second-wave participants arising from four seeds . Completion time for the survey ranged between 7 and 36 minutes. Despite repeated reminders, no further people were recruited. While New Zealand wheelchair user numbers are unknown, an estimated 14% of people have physical impairments that limited mobility. The 19 respondents generated from adopting the RDS methodology here thus represents a negligible fraction of wheelchair users in New Zealand, and an insufficient number to ensure equilibrium. While successful in other hard-to-reach populations, applying RDS methodology to wheelchairs users requires further consideration. Formative research exploring areas of network characteristics, acceptability of RDS, appropriate incentive options, and seed selection amongst wheelchair users is needed.

Changes in Family Cohesion and Acculturative Stress among Recent Latino Immigrants

Family relationships can serve as an important source of support during the acculturation process; yet, how the stress related to acculturation, or acculturative stress, may impact family functioning across time is not clear. Participants (N = 479) between the ages of 18 and 34 were recruited using respondent-driven sampling methodology. Findings suggest family cohesion decreased over time; however, it decreased less for those reporting more acculturative stress. The implication is that for those Latino immigrants who struggle to adapt to their new host culture, family remains a source of support more so than for those who do not struggle as much.

A qualitative analysis of peer recruitment pressures in respondent driven sampling: Are risks above the ethical limit?

BackgroundThis paper examines peer recruitment dynamics through respondent driven sampling (RDS) with a sample of injection drug users in Hartford, CT to understand the strategies participants use to recruit peers into a study and the extent to which these strategies may introduce risks above the ethical limit despite safeguards in RDS. MethodsOut of 526 injection drug users who participated in a mixed-method RDS methodology evaluation study, a nested sample of 61 participants completed an in-depth semi-structured interview at a 2-month follow-up to explore their experiences with the recruitment process. ResultsFindings revealed that participants used a variety of strategies to recruit peers, ranging from one-time interactions to more persistent strategies to encourage participation (e.g., selecting peers that can easily be found and contacted later, following up with peers to remind them of their appointment, accompanying peers to the study site, etc.). Some participants described the more persistent strategies as helpful, while some others experienced these strategies as minor peer pressure, creating a feeling of obligation to participate. Narratives revealed that overall, the probability of experiencing study-related risks remains relatively low for most participants; however, a disconcerting finding was that higher study-related risks (e.g., relationship conflict, loss of relationship, physical fights, violence) were seen for recruits who participated but switched coupons or for recruits who decided not to participate in the study and did not return the coupon to the recruiter. ConclusionsFindings indicate that peer recruitment practices in RDS generally pose minimal risk, but that peer recruitment may occasionally exceed the ethical limit, and that enhanced safeguards for studies using peer recruitment methods are recommended. Suggestions for possible enhancements are described.

Using Respondent Driven Sampling to Recruit Sexual Minority Women

ABSTRACT: Purpose: To describe: (1) recruitment of a community sample of sexual minority women (SMW) using respondent driven sampling (RDS), (2) and how RDS was modified to reach target recruitment goals, and (3) characteristics of successful recruiters. Methods: We compared the rates of recruitment using RDS and two modifications of RDS that we developed during our recruitment of SMW in Chicago. Key demographics of successful recruiters are described. Results: Using RDS without modifying the standard methodology provided the best rate of recruitment, but moved too slowly to be cost effective. Modifications proved necessary to meet recruitment goals. Participants who successfully recruited others tended to be younger, were African-American, have a high school education or less, and have an income of $20,000 per year or less. Conclusion: Researchers using RDS to recruit SMW may need to consider modifying RDS methodology. Flexibility and adequate staff resources are important. Using RDS to fill specific cells required to obtain a diverse sample may be difficult given the nature of RDS and the demographic characteristics of successful recruiters.

Gay and bisexual men engage in fewer risky sexual behaviors while traveling internationally: a cross-sectional study in San Francisco

BackgroundInternational travel poses potential challenges to HIV prevention. A number of studies have observed an association between travel and behavioural disinhibition. In the present study, we assessed differences in sexual...