Factors Associated with Productive Recruiting in a Respondent-Driven Sample of Men who Have Sex with Men in Vancouver, Canada

Recruiting Black and Latina/Hispanic Transgender Women for HIV Research: Implementation of Respondent-Driven Sampling and Factors Associated with Peer Recruitment

Purpose

We aim to examine if respondent-driven sampling (RDS) is a feasible and efficient method to recruit Black and Latina/Hispanic transgender women into HIV research.

Methods

As part of the National HIV Behavioral Surveillance Study among transgender women in New York City in 2019, RDS was implemented with a focus on recruiting Black and Latina/Hispanic transgender women. We identified factors independently associated with (1) peer recruitment and (2) presenting to the study with a photo coupon.

Results

A total of 269 transgender women were enrolled, 94% of whom were Black or Latina/Hispanic. In terms of peer recruitment, 47% recruited at least one eligible peer. Compared with those who were aged 18-29 years, those aged 30-39 years (adjusted prevalence ratio [aPR]: 2.04; 95% confidence interval [CI]: 1.35-3.07) and those aged 50 years or older (aPR: 1.97; 95% CI: 1.32-2.94) were more likely to recruit an eligible peer. Peer recruitment was also associated with utilizing HIV prevention services in the past 12 months (aPR: 1.62; 95% CI: 1.18-2.23). We did not find any differences in presenting the study with a photo recruitment coupon versus a physical recruitment coupon.

Conclusion

RDS was feasible and efficient in recruiting Black and Latina/Hispanic transgender women. Providing gender-affirming environments as well as allowing peer recruitment through photo coupons may have facilitated peer recruitment and study participation. Our findings regarding factors associated with peer recruitment could aid in future study design and may help in addressing the lack of HIV research among Black and Latina/Hispanic transgender women.

Examining differential success in recruitment using respondent driven sampling (RDS) in a multi-site study of gay, bisexual and other men who have sex with men

BACKGROUND

The Engage Study is a longitudinal biobehavioral cohort study of gay, bisexual and other men who have sex with men (GBM) in Toronto, Montreal, and Vancouver. Baseline data (2,449 participants) were collected from February 2017 - August 2019 using respondent-driven sampling (RDS). Recruitment in Montreal required fewer seeds, had a much shorter recruitment period, and recruited the largest sample.

METHODS

To better understand why RDS recruitment was more successful in Montreal compared to other sites, we conducted an analysis to examine RDS recruitment characteristics for GBM in each of the three study sites, explore demographic characteristics and measures of homophily, that is, the tendency of individuals to recruit other study participants who are like themselves, and compared motivations for study participation.

RESULTS

Montreal had the greatest proportion of participants over the age of 45 (29.1% in Montreal, 24.6% in Vancouver, and 21.0% in Toronto) and the highest homophily for this age group, but homophily was high across the three cities. Montreal also reported the lowest percentage of participants with an annual income greater or equal to $60,000 (7.9% in Montreal, 13.1% in Vancouver and 10.6% in Toronto), but homophily was similar across all three cities. The majority of participants indicated interest in sexual health and HIV as the main reason for participating (36.1% in Montreal, 34.7% in Vancouver, and 29.8% in Toronto). Financial interest as the main reason for participation was low (12.7% in Montreal, 10.6% in Vancouver, and 5.7% in Toronto).

CONCLUSION

Taken together, although we found some differences in study demographic characteristics and homophily scores, we were unable to fully explain the different recruitment success based on the data available. Our study underlines the fact that success of RDS implementation may vary by unknown factors, and that researchers should be proactive and flexible to account for variability.

Virological suppression among gay, bisexual, and other men who have sex with men living with HIV in Vancouver, Canada: A longitudinal cohort study from 2012-2017

INTRODUCTION

In 2010, British Columbia (BC) implemented HIV Treatment as Prevention (TasP) as policy. We examined trends in virologic suppression and determinants of significant viremia among a prospective biobehavioural cohort of men who have sex with men (gbMSM) in Vancouver from 2012-2017.

METHODS

Respondent-driven sampling was used to recruit sexually active gbMSM (≥16 years) who completed biannual study visits with a computer-assisted self-interview and clinical CD4 and viral load (VL) testing. We linked participant data with the BC HIV Drug Treatment Program to obtain antiretroviral dispensing and VL data. We conducted a trend analysis of VL suppression using univariable generalized estimating equation (GEE) multi-level modelling and multivariable GEE to identify factors associated with episodes of VL ≥200 copies/mL.

RESULTS

Of 774 participants, 223 were living with HIV at baseline and 16 were diagnosed during follow-up (n = 239). We observed a significant trend towards reduced levels of unsuppressed VL (>200 copies/mL) from 22% (07/2012-12/2012) to 12% (07/2016-12/2016) (OR:0.87; 95%CI:0.83-0.91 for each 6-month period). Among those with at least one follow-up visit, (n = 178, median follow-up = 3.2 years, median age = 46.9 years), younger age (aOR:0.97; 95%CI:0.94-0.99, per year), ecstasy use (aOR:1.69; 95%CI:1.13-2.53), crystal methamphetamine use (aOR:1.71; 95%CI:1.18-2.48), seeking sex via websites (aOR:1.46; 95%CI:1.01-2.12), and lower HIV treatment optimism (aOR:0.94; 95%CI:0.90-0.97) were associated with episodes of elevated viremia.

CONCLUSIONS

During a period when TasP policy was actively promoted, we observed a significant trend towards reduced levels of unsuppressed VL. Continued efforts should promote HIV treatment optimism and engagement, especially among younger gbMSM and those who use ecstasy and crystal methamphetamine.

Undetectable or Unknown? A Longitudinal Event-Level Analysis of Disclosure of HIV Serostatus and Undetectability Among Gay, Bisexual, and Other Men Who have Sex with Men (gbMSM) in Metro Vancouver

We examined temporal trends and factors associated with reporting partner's serostatus and viral load among a sample of gay, bisexual and other men who have sex with men (gbMSM) in Vancouver, Canada. Participants were recruited using respondent-driven sampling and we collected prospective cohort data from 09/2014 to 02/2017 using a computer-assisted questionnaire and nurse-administered STI/HIV testing. Our study included 481 participants reporting on 3780 sexual events. Among HIV-negative/unknown gbMSM we found a trend towards decreased proportions of sexual events reporting an unknown HIV-status partner (42-19%; p =  < 0.001) and found increased proportions among gbMSM living with HIV (11-27%; p = 0.043). More participants living with HIV reported sex with undetectable partners, compared to HIV-negative/unknown participants (14.8% versus 5%). Our multivariable model found that compared with unknown status partners, undetectable partners were older, were from longer sexual relationships and were more likely to engage in condomless anal sex. Findings indicate that HIV-negative gbMSM seem more aware of the serostatus of their partners over time, but knowledge of partners' viral load over time was not significant. Further research should assess the degree to which new campaigns such as Undetectable = Untransmittable (U = U) are associated with discussions about HIV disclosure and viral load status.

The Co-Evolution of Network Structure and PrEP Adoption among a Large Cohort of PrEP Peer Leaders: Implications for Intervention Evaluation and Community Capacity-Building

Background: Peer leader interventions are effective strategies for promoting prevention behaviors in communities at risk for HIV, yet little is known about their effects on the social and behavioral dynamics of peer leaders themselves. Methods: Using data from PrEP Chicago, an RCT PrEP for prevention intervention for young Black MSM (YBMSM), we apply stochastic actor-based models to longitudinally model the impact of study participation on the online friendship and PrEP adoption dynamics among a network of peer leaders (n = 174) and a network of control group counterparts (n = 166). Results: Peer leaders assigned to the same leadership training workshop were more likely to form new Facebook friendships with one another, whereas control participants assigned to the same attention control workshop were no more or less likely to form new friendships. Further, peer leaders with greater PrEP intentions and those living with HIV were more active in forming new friendships with other peer leaders, effects not found in the control network. PrEP adoption was not influenced by network dynamics in either group. Conclusions: The implications of these findings are discussed through the lens of community-capacity building and the role that peer leader interventions and the networks they engage can impact public health.

Correlates of Alcohol-Using Network Size Among Men Who Have Sex with Men in San Francisco, CA

Men who have sex with men (MSM) have a high prevalence of hazardous alcohol consumption. While network-level characteristics such as social network size have been indicated as upstream determinants of alcohol use in general population samples, no studies have examined factors associated with alcohol using network size (ANS), among MSM.This secondary analysis examined demographic, substance use, and sexual behavior correlates of ANS using data from a diverse sample of alcohol-using MSM in San Francisco (N = 252). Associations were calculated using multivariable negative binomial regression, adjusting for age, race, education, and employment.The median ANS was 10. Factors associated with larger ANS in multivariable analyses included identifying as Hispanic/Latino, having completed a college education or higher, having a higher Alcohol Use Disorders Identification Test (AUDIT) score, having a greater number of sexual partners, polysubstance use, and being unaware of one's own HIV status. Factors associated with smaller ANS included being between 18 and 24 years of age, reporting a low income, and having any lifetime history of injection drug use.For MSM, ANS was associated with increased likelihood of hazardous alcohol use, as well specific individual-level substance use and sexual risk behaviors. These results highlight the role of ANS in hazardous alcohol consumption and sexually transmitted infection transmission among MSM. These results also indicate ways that research and intervention programs aimed at reducing alcohol use among MSM might be improved through network-based recruitment or engagement. Finally, these results suggest the need for further research on HIV-unknown MSM.

Individual and Social Network Structure Characteristics Associated with Peer Change Agent Engagement and Impact in a PrEP Intervention

Interventions that utilize the influence of peer change agents (PCAs) have been shown to be effective strategies for engaging key populations in HIV prevention. To date, little is known about the characteristics of PCAs associated with their effectiveness. Drawing on data from a peer leader PrEP intervention for young Black men who have sex with men (YBMSM) (N = 423), we evaluated the effects of experiential (i.e., living with HIV, PrEP awareness, PrEP use), psychographic (i.e., self-perceived leadership, innovativeness), and network (i.e., degree centrality, eigenvector centrality, and brokerage) characteristics on three effectiveness outcomes: (1) recruiting peers into the study; (2) completing "booster" sessions; and (3) linking peers to PrEP care. For each outcome, multivariable regressions were performed. On average, PCAs recruited 0.89 peers, completed 1.99 boosters, and had 1.33 network peers linked to PrEP care. Experiential factors: Prior PrEP awareness was positively associated with booster completion. Network factors: Being a network broker (i.e., connecting otherwise disconnected communities) was positively associated with peer recruitment but negatively associated with linking peers to PrEP, and degree centrality (i.e., the number of network connections someone has) and eigenvector centrality (i.e., being connected to well-connected network associates) were positively associated with linking peers to PrEP. Psychographic characteristics were not associated with any outcome. These findings can be used to inform PCA selection and to identify subpopulations who require additional support to excel as PCAs.

Implementing Respondent-Driven Sampling to Recruit Women Who Exchange Sex in New York City: Factors Associated with Recruitment and Lessons Learned

Respondent-driven sampling (RDS) relies on productive peer recruitment to capture hidden populations. Domestic studies have identified characteristics of productive recruitment among RDS samples of men who have sex with men and persons who use drugs, but not of women who exchange sex, a group vulnerable to HIV infection. We examined sociodemographic-, behavioral-, exchange-sex-, and protocol-related factors associated with recruitment among seeds (n = 25) and peers (n = 297) in the 2016 New York City National HIV Behavioral Surveillance Study cycle focused on women who exchange sex. Recruiter productivity was significantly associated with not having been recently incarcerated, lower rate of HIV testing, and larger exchange sex networks among seeds, and with HIV-prevention services usage among peers. We describe challenges and lessons learned from implementing RDS in this population. Our study identifies seed characteristics and protocol improvements researchers can utilize when implementing future RDS studies among women who exchange sex.

Exploring the role of sex-seeking apps and websites in the social and sexual lives of gay, bisexual and other men who have sex with men: a cross-sectional study

Background The objective of this study was to explore the relationship between online sex-seeking, community/social attachment and sexual behaviour.

METHODS

Respondent-driven sampling was used to recruit 774 sexually active gay and bisexual men in Vancouver, Canada, aged ≥16 years. Multivariable logistic regression compared men who had used online sex-seeking apps/websites in the past 6 months (n=586) with those who did not (n=188).

RESULTS

Multivariable results showed that online sex seekers were more likely to be younger [adjusted odds ratio (aOR)=0.95, 95% CI: (0.93-0.96)], college educated [aOR=1.60, 95% CI: (1.07, 2.40)], have more Facebook friends [aOR=1.07, 95% CI: (1.01, 1.13)], spend more social time with other gay men [aOR=1.99, 95% CI: (1.33-2.97)], and were less likely to identify emotionally with the gay community [aOR=0.93, 95% CI: (0.86-1.00)]. Further, they had displayed high sensation-seeking behaviour [aOR=1.08, 95% CI: (1.03-1.13)], were more likely to engage in serodiscordant/unknown condomless anal sex [aOR=2.34, 95% CI: (1.50-3.66)], use strategic positioning [aOR=1.72, 95% CI: (1.08-2.74)], ask their partner's HIV-status prior to sex [aOR=2.06, 95% CI: (1.27-3.37)], and have ever been tested for HIV [aOR=4.11, 95% CI: (2.04-8.29)].

CONCLUSION

These findings highlight the online and offline social behaviour exhibited by gay and bisexual men, pressing the need for pro-social interventions to promote safe-sex norms online. We conclude that both Internet and community-based prevention will help reach app/web users.

HIV leadership programming attendance is associated with PrEP and PEP awareness among young, gay, bisexual, and other men who have sex with men in Vancouver, Canada

BACKGROUND

Young gay, bisexual, and other men who have sex with men (YGBM) may have reduced engagement and knowledge of HIV care and biomedical HIV prevention strategies, such as pre-exposure prophylaxis (PrEP), post-exposure prophylaxis (PEP), and Treatment as Prevention (TasP), compared with adult GBM. We sought to understand differences in HIV prevention awareness, health care access, and service utilization between youth (16-29 years) and adult (≥30 year) GBM, as well as factors associated with attendance in HIV leadership programming among YGBM living in the publicly funded PrEP setting of Vancouver, Canada.

METHODS

Sexually-active GBM were recruited using respondent-driven sampling (RDS) from February 2012 to February 2015. Participants completed an in-person computer-assisted self-interview every 6 months, up to February 2017, with questions on sociodemographic factors, awareness of biomedical HIV prevention strategies, and an HIV treatment optimism-skepticism scale. Participants were asked if they had ever attended either of two HIV-leadership programs designed for YGBM. Both programs involve multiple GBM-led education and social networking sessions operated by community-based organizations in Vancouver. Multivariable Glimmix confounder models assessed differences between youth and adult GBM. Among younger men, bivariate analyses examined factors associated with HIV-leadership program attendance.

RESULTS

Of 698 GBM who enrolled in the longitudinal study, 36.8% were less than 30 years old at the first study visit. After controlling for gender identification, sexual orientation, HIV status, and income in the past 6 months, younger GBM (n = 257/698) had lower awareness of biomedical HIV prevention strategies and less HIV treatment optimism compared with older GBM (n = 441/698). Among younger GBM who attended HIV-leadership programs (n = 50), greater awareness of biomedical HIV prevention strategies and higher HIV treatment optimism were reported, compared with non-attendees.

CONCLUSION

Younger GBM, who are disproportionately affected by the HIV epidemic, are less aware of new prevention technologies than older GBM, but attending peer-based HIV-leadership programs ameliorates age-disparities in HIV-prevention knowledge and treatment optimism.

Substance Use as a Mechanism for Social Inclusion among Gay, Bisexual, and Other Men Who Have Sex with Men in Vancouver, Canada

Background: Previous research demonstrates that substance use preferences and social-sexual environments are highly interrelated for gay, bisexual, and other men who have sex with men (gbMSM). Objective: We conducted a qualitative study to explore the socio-cultural context of substance use among local gbMSM communities in Metro Vancouver, Canada. Methods: Twenty gbMSM were purposively sampled from the larger Momentum Health Study cohort, a sexual health study of gbMSM in Greater Vancouver. Participants were demographically diverse in terms of HIV serostatus, age, income, ethnicity, and area of residence within the city and neighboring suburbs. Community maps generated by participants during formative research served as prompts for semi-structured interviews which were audio recorded and transcribed verbatim. Thematic analysis identified three themes of common experience. Results: First, participants indicated that substance use is intrinsically social in Vancouver gbMSM communities and that it functions as both a means of social inclusion and exclusion. Second, a distinction was made between types of substances and the location and context of their use, with specific substances having particular uses and meanings. Third, analysis suggested that gbMSM change their substance use over the life course and that this is affected by shifting priorities as people age. Discussion: For Vancouver gbMSM communities, substance use serves several social-cultural functions and can simultaneously serve as both a potential facilitator and barrier for community connection. Future research and health programing should consider venue and context specific messaging and recognize the heterogeneity of substance use within the larger gbMSM population.

Prevalence and correlates of hazardous alcohol consumption and binge drinking among men who have sex with men (MSM) in San Francisco

Objectives

To describe heavy alcohol use patterns and correlates in a diverse sample of MSM.

Methods

We used respondent-driven sampling (RDS) to enroll 252 alcohol-using MSM in San Francisco from March 2015-July 2017. We examined heavy alcohol use patterns and conducted RDS-adjusted multivariable analyses to characterize correlates of hazardous alcohol consumption and binge drinking.

Results

RDS-adjusted prevalence of weekly and at least weekly binge drinking was 24.9% and 19.3%, respectively. Hazardous consumption was common; prevalence of mid- and high-levels of hazardous drinking was 11.4% and 29.9%, respectively. In multivariable analyses, identifying as Hispanic/Latino or mixed/other race; being moderately or extremely interested in reducing alcohol use; ever receiving alcohol treatment; using ecstasy; reporting syphilis diagnosis; and having more than 5 male partners were independently associated with hazardous alcohol consumption. Less hazardous consumption was associated with having a bachelor's degree or completing post-graduate studies; and not being in a relationship. Reporting chlamydia infection; being somewhat, moderately or extremely interested in reducing alcohol use; and having multiple male sex partners were associated with higher odds of at least weekly binge drinking. Lower odds of binge drinking were associated with completing post-graduate studies. Moreover, for the outcomes of hazardous alcohol consumption and binge-drinking, we observed significant interaction effects between race/ethnicity and interest in reducing alcohol, past receipt of alcohol treatment, use of ecstasy, syphilis diagnosis, and number of male partners.

Conclusion

Among alcohol-using MSM in San Francisco, heavy drinking patterns were common and independently associated with greater number of male sexual partners and sexually transmitted infections (STI). Moreover, significant racial/ethnic and socioeconomic disparities related to heavy alcohol use were observed and race/ethnicity modified the effect of the risk factors associated with these outcomes. These findings underscore the need to develop more MSM-specific interventions that jointly address heavy alcohol use and HIV/STI risk, as well as culturally-tailored and targeted strategies to alleviate health disparities.

Assessing the longitudinal stability of latent classes of substance use among gay, bisexual, and other men who have sex with men

BACKGROUND

Association between substance use and HIV-risk among gay and bisexual men (GBM) is well documented. However, their substance use patterns are diverse, and it is unknown whether self-reported use patterns are stable over time.

METHODS

Sexually-active GBM, aged >16 years, were recruited in Metro Vancouver using respondent-driven sampling and followed across 5 study visits at six-month intervals (n = 449). To identify distinct patterns of substance use and their longitudinal stability, Latent Transition Analysis (LTA) was conducted for drugs reported by at least 30 participants. Intraclass correlation coefficients (ICC) quantified the stability of class assignments.

RESULTS

Six classes characterizing 'limited drug use' (i.e., low use of all drugs, except alcohol), 'conventional drug use' (i.e., use of alcohol, marijuana, and tobacco), 'club drug use' (i.e., use of alcohol, cocaine, and psychedelics), 'sex drug use' (i.e., use of alcohol, crystal meth, GHB, poppers, and erectile dysfunction drugs), 'street drug use' (i.e., use of alcohol and street opioids) and 'assorted drug use' (i.e., use of most drugs) were identified. Across five visits (2.5 years), 26.3% (n = 118/449) of GBM transitioned between classes. The prevalence of limited use trended upwards (Baseline:24.5%, Visit 5:28.3%, p < 0.0001) and assorted use trended downwards (13.4%-9.6%, p = 0.001). All classes had strong longitudinal stability (ICC > 0.97).

CONCLUSION

The stability of latent substance use patterns highlight the utility of these measures in identifying patterns of substance use among people who use drugs - potentially allowing for better assessment of these groups and interventions related to their health.

Statistical adjustment of network degree in respondent-driven sampling estimators: venue attendance as a proxy for network size among young MSM

We introduce a new venue-informed network degree measure, which we applied to respondent-driven sampling (RDS) estimators. Using data collected from 746 young MSM in 2014-2016 in Chicago, IL, and Houston, TX, we estimated the population seroprevalence of HIV and syphilis and risk/protective behaviors, using RDS estimates with self-reported network size as a standard degree measure as well as our proposed venue-informed degree measure. The results indicate that the venue-informed degree measure tended to be more efficient (smaller variance) and less biased than the other measure in both cities sampled. Venue attendance-adjusted network size may provide a more reliable and accurate degree measure for RDS estimates of the outcomes of interest.

Patterns of Online and Offline Connectedness Among Gay, Bisexual, and Other Men Who Have Sex with Men

This study examined patterns of connectedness among 774 sexually-active gay, bisexual, and other men who have sex with men (GBM), aged ≥ 16 years, recruited using respondent-driven sampling in Metro Vancouver. Latent class analysis examined patterns of connectedness including: attendance at gay venues/events (i.e., bars/clubs, community groups, pride parades), social time spent with GBM, use of online social and sex seeking apps/websites, and consumption of gay media. Multinomial regression identified correlates of class membership. A three-class LCA solution was specified: Class 1 "Socialites" (38.8%) were highly connected across all indicators. Class 2 "Traditionalists" (25.7%) were moderately connected, with little app/website-use. Class 3 "Techies" (35.4%) had high online connectedness and relatively lower in-person connectedness. In multivariable modelling, Socialites had higher collectivism than Traditionalists, who had higher collectivism than Techies. Socialites also had higher annual incomes than other classes. Techies were more likely than Traditionalists to report recent serodiscordant or unknown condomless anal sex and HIV risk management practices (e.g., ask their partner's HIV status, get tested for HIV). Traditionalists on the other hand were less likely to practice HIV risk management and had lower HIV/AIDS stigma scores than Socialites. Further, Traditionalists were older, more likely to be partnered, and reported fewer male sex partners than men in other groups. These findings highlight how patterns of connectedness relate to GBM's risk management.

Protective Factors Among Transgender and Gender Variant Youth: A Systematic Review by Socioecological Level

Transgender and gender variant (GV) youth experience elevated risk for poor health and academic outcomes due mainly to social experiences of stigma and discrimination. To supplement the growing evidence on health risks encountered by transgender/GV youth, we identified factors theorized to be protective for these youth across all four levels of Bronfenbrenner's socioecological model (individual, relationship, community, societal). We conducted a systematic search of peer-reviewed research. The articles included in this review were published in peer-reviewed journals in English or Spanish between 1999 and 2014, analyzed data from a sample or subsample of transgender or GV participants with a mean age between 10 and 24 years, and examined the relationship of at least one theorized protective factor to a health or behavioral outcome. Twenty-one articles met inclusion criteria. Transgender/GV youth in included articles ranged from 11 to 26 years of age, were racially/ethnically diverse, and represented varied gender identities. Within these articles, 27 unique protective factors across four levels of the ecological model were identified as related to positive health and well-being. Self-esteem at the individual level, healthy relationships with parents and peers at the relationship-level, and gay-straight alliances at the community level emerged as protective factors across multiple studies. Our findings underscore the relative lack of research on transgender/GV youth and protective factors. Novel recruitment strategies for transgender/GV youth and better measurement of transgender identities are needed to confirm these protective relationships and identify others. Growth in these areas will contribute to building a body of evidence to inform interventions.

Identification of Homophily and Preferential Recruitment in Respondent-Driven Sampling

Respondent-driven sampling (RDS) is a link-tracing procedure used in epidemiologic research on hidden or hard-to-reach populations in which subjects recruit others via their social networks. Estimates from RDS studies may have poor statistical properties due to statistical dependence in sampled subjects' traits. Two distinct mechanisms account for dependence in an RDS study: homophily, the tendency for individuals to share social ties with others exhibiting similar characteristics, and preferential recruitment, in which recruiters do not recruit uniformly at random from their network alters. The different effects of network homophily and preferential recruitment in RDS studies have been a source of confusion and controversy in methodological and empirical research in epidemiology. In this work, we gave formal definitions of homophily and preferential recruitment and showed that neither is identified in typical RDS studies. We derived nonparametric identification regions for homophily and preferential recruitment and showed that these parameters were not identified unless the network took a degenerate form. The results indicated that claims of homophily or recruitment bias measured from empirical RDS studies may not be credible. We applied our identification results to a study involving both a network census and RDS on a population of injection drug users in Hartford, Connecticut (2012-2013).