Using dual capture/recapture studies to estimate the population size of persons who inject drugs (PWID) in the city of Hai Phong, Vietnam.

Background: Good estimates of key population sizes are critical for appropriating resources to prevent HIV infection. We conducted two capture/recapture studies to estimate the number of PWID currently in Hai Phong, Vietnam.

Methods: A 2014 respondent-driven sampling (RDS) survey served as one capture, and distribution of cigarette lighters at drug use "hotspots" in 2016 served as another "capture.

Using Respondent-Driven Sampling to Recruit Illegal Drug Purchasers to Evaluate a Drug Market Intervention.

Background: Violent drug markets are not as prominent as they once were in the United States, but they still exist and are associated with significant crime and lower quality of life. The drug market intervention (DMI) is an innovative strategy that uses focused deterrence, community engagement, and incapacitation to reduce crime and disorder associated with these markets. Although studies show that DMI can reduce crime and overt drug activity, one perspective is prominently missing from these evaluations: those who purchase drugs.

Integrated respondent-driven sampling and peer support for persons who inject drugs in Haiphong, Vietnam: a case study with implications for interventions.

Combined prevention for HIV among persons who inject drugs (PWID) has led to greatly reduced HIV transmission among PWID in many high-income settings, but these successes have not yet been replicated in resource-limited settings. Haiphong, Vietnam experienced a large HIV epidemic among PWID, with 68% prevalence in 2006. Haiphong has implemented needle/syringe programs, methadone maintenance treatment (MMT), and anti-retroviral treatment (ART), but there is an urgent need to identify high-risk PWID and link them to services.

Design and baseline findings of a large-scale rapid response to an HIV outbreak in people who inject drugs in Athens, Greece: the ARISTOTLE programme.

Aims: To (i) describe an intervention implemented in response to the HIV-1 outbreak among people who inject drugs (PWIDs) in Greece (ARISTOTLE programme), (ii) assess its success in identifying and testing this population and (iii) describe socio-demographic characteristics, risk behaviours and access to treatment/prevention, estimate HIV prevalence and identify risk factors, as assessed at the first participation of PWIDs.

Design: A 'seek, test, treat, retain' intervention employing five rounds of respondent-driven sampling.

Setting: Athens, Greece (2012-13).

Assessing the assumptions of respondent-driven sampling in the national HIV Behavioral Surveillance System among injecting drug users.

Several assumptions determine whether respondent-driven sampling (RDS) is an appropriate sampling method to use with a particular group, including the population being recruited must know one another as members of the group (i.e., injection drug users [IDUs] must know each other as IDUs) and be networked and that the sample size is small relative to the overall size of the group.

Parsing social network survey data from hidden populations using stochastic context-free grammars.

Background: Human populations are structured by social networks, in which individuals tend to form relationships based on shared attributes. Certain attributes that are ambiguous, stigmatized or illegal can create a OhiddenO population, so-called because its members are difficult to identify. Many hidden populations are also at an elevated risk of exposure to infectious diseases.

Simultaneous recruitment of drug users and men who have sex with men in the United States and Russia using respondent-driven sampling: sampling methods and implications.

The Sexual Acquisition and Transmission of HIV Cooperative Agreement Program (SATHCAP) examined the role of drug use in the sexual transmission of the human immunodeficiency virus (HIV) from traditional high-risk groups, such as men who have sex with men (MSM) and drug users (DU), to lower risk groups in three US cities and in St. Petersburg, Russia. SATHCAP employed respondent-driven sampling (RDS) and a dual high-risk group sampling approach that relied on peer recruitment for a combined, overlapping sample of MSM and DU.

HIV infection, sexual risk behavior, and substance use among Latino gay and bisexual men and transgender persons.

Objectives: We examined HIV prevalence and the socioeconomic correlates of HIV infection, sexual risk behaviors, and substance use among Latino gay and bisexual men and transgender persons in Chicago and San Francisco.

Methods: Data were collected from a sample of 643 individuals (Chicago: n=320; San Francisco: n=323) through respondent-driven sampling and computer-assisted self-administered interviews.

Results: HIV prevalence in San Francisco (0.

Ethical and regulatory considerations in HIV prevention studies employing respondent-driven sampling.

Objective: To review the scientific, ethical, and regulatory literature because no official guidance exists on remuneration for participant-driven recruitment or on investigators' responsibilities for informing participants of their discordant partnerships.

Methods: We reviewed the studies that used RDS to recruit injection-drug users (IDUs), 1995-2006, and the relevant scientific, ethical, and regulatory literature that shed light on arguments for and against practices that can be used in studies employing RDS.

Results: Concerns that payments can be used to buy drugs or can subvert altruistic motivations for study participation are not supported by the literature.

High-risk sexual and drug using behaviors among male injection drug users who have sex with men in 2 Mexico-US border cities.

Objectives: The population of Latino men who have sex with men (MSM) and who are also injection drug users (IDUs) is understudied. We explored risk behaviors of MSM/IDUs compared with other male IDUs in 2 Mexican border cities.

Study Design: In 2005, IDUs who had injected within the previous 30 days were recruited using respondent-driven sampling (RDS) in Tijuana and Ciudad Juárez.

The transition from injection to non-injection drug use: long-term outcomes among heroin and cocaine users in New York City.

Aims: To characterize heroin and cocaine users in New York City who have changed from injection to non-injection drug administration and to identify factors associated with long-term non-injection use.

Design: Two cross-sectional studies of heroin and cocaine users in New York City.

Settings And Participants: New admissions were recruited at drug abuse treatment programs (2000-04) and respondent-driven sampling was used to recruit drug users from the community (2004).

Convergence of HIV seroprevalence among injecting and non-injecting drug users in New York City.

Objective: To compare HIV prevalence among injecting and non-injecting heroin and cocaine users in New York City. As HIV is efficiently transmitted through the sharing of drug-injecting equipment, HIV infection has historically been higher among injecting drug users.

Design: Two separate cross-sectional surveys, both with HIV counseling and testing and drug use and HIV risk behavior questionnaires.

Respondent-driven sampling in a study of drug users in New York City: notes from the field.

Beth Israel Medical Center (BIMC), in collaboration with the Centers for Disease Control (CDC) and the New York State Department of Health (NYSDOH), used respondent-driven sampling (RDS) in a study of HIV seroprevalence among drug users in New York City in 2004. We report here on operational issues with RDS including recruitment, coupon distribution, storefront operations, police and community relations, and the overall lessons we learned. Project staff recruited eight seeds from a syringe exchange in Lower Manhattan to serve as the initial study participants.

Effectiveness of respondent-driven sampling for recruiting drug users in New York City: findings from a pilot study.

A number of sampling methods are available to recruit drug users and collect HIV risk behavior data. Respondent-driven sampling (RDS) is a modified form of chain-referral sampling with a mathematical system for weighting the sample to compensate for its not having been drawn randomly. It is predicated on the recognition that peers are better able than outreach workers and researchers to locate and recruit other members of a "hidden" population.

From networks to populations: the development and application of respondent-driven sampling among IDUs and Latino gay men.

One of the challenges in studying HIV-risk behaviors among gay men is gathering information from a non-biased sample, as traditional probability sampling methods cannot be applied in gay populations. Respondent-Driven Sampling (RDS) has been proposed as a reliable and bias-free method to recruit "hidden" populations, such as gay men. The aim of this study is to assess the feasibility and effectiveness of RDS to sample Latino gay men and transgender persons.

Review of sampling hard-to-reach and hidden populations for HIV surveillance.

Adequate surveillance of hard-to-reach and 'hidden' subpopulations is crucial to containing the HIV epidemic in low prevalence settings and in slowing the rate of transmission in high prevalence settings. For a variety of reasons, however, conventional facility and survey-based surveillance data collection strategies are ineffective for a number of key subpopulations, particularly those whose behaviors are illegal or illicit. This paper critically reviews alternative sampling strategies for undertaking behavioral or biological surveillance surveys of such groups.

Increasing drug users' adherence to HIV treatment: results of a peer-driven intervention feasibility study.

Active drug users with HIV infection suffer from both low utilization of, and adherence to, primary care. Combining drug treatment and primary care on-site reduces these problems significantly because it creates a social support structure; treatment program staffs can monitor patients' adherence and provide ongoing encouragement. But in the United States, only a very small minority of HIV + drug users receive this demonstrably effective form of care.