Implementation and analysis of respondent driven sampling: lessons learned from the field.
Explore the source record for details and available documents.
Centers for Disease Control and Prevention, U.S.↗
Biomedical subjects
Tobi Saidel
Publications and source records attributed to Tobi Saidel.
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. Non-probability sampling approaches such as facility-based sentinel surveillance and snowball sampling are the simplest to carry out, but are subject to a high risk of sampling/selection bias. Most of the probability sampling methods considered are limited in that they are adequate only under certain circumstances and for some groups. One relatively new method, respondent-driven sampling, an adaptation of chain-referral sampling, appears to be the most promising for general applications. However, as its applicability to HIV surveillance in resource-poor settings has yet to be established, further field trials are needed before a firm conclusion can be reached.
Epidemiologic Methods↗
Intravenous drug use among street-based sex workers: a high-risk behavior for HIV transmission.
BACKGROUND: HIV prevalence among sex workers in Ho Chi Minh City has increased rapidly, from 6.5% in 1999 to 18.1% in 2000. This study examined whether injecting drug use among street-based sex workers (SSWs) in Ho Chi Minh City is a high-risk factor for HIV infection. GOAL: The goal of this study was to determine the correlates and prevalence of intravenous drug users among SSWs in Ho Chi Minh City. STUDY DESIGN: A cross-sectional study was conducted among SSWs in Ho Chi Minh City during December 2000. The SSWs were interviewed and tested for HIV-1. RESULTS: HIV-1 seroprevalence was 16.3%. Regression analysis indicated that injecting drugs and being younger than 25 years of age were independently associated with HIV seropositivity. CONCLUSION: Young SSWs who inject drugs are at the greatest risk of contracting HIV and acting as a bridge for HIV to the sexually active population.
Adolescent↗
HIV, STIs, and sexual behaviors among men who have sex with men in Phnom Penh, Cambodia.
A probability sample of 206 men who have sex with men from 16 sites in Phnom Penh were surveyed about sexual behaviors and tested for HIV and sexually transmitted infections (STIs). HIV and syphilis prevalence was 14.4% and 5.5%, respectively. Out of the total sample, 81% reported anal sex with any male partners in the past 6 months, and 61.2% reported having had vaginal sex. In the past 6 months, 82.8% of the sample reported having male partners who paid them to have sex. Self-reported sexual orientation did not match well with self-reported sexual behavior. Significant risk factors for HIV infection were anal sex with multiple partners, unprotected vaginal sex with commercial female partners in the past month, and any STI. Complex sexual networks indicate that men who have sex with men act as a bridge between higher and lower HIV prevalence populations. Better prevention efforts structured around behaviors rather than sexual identities are needed.
Adult↗
Growing in silence: selected regions and countries with expanding HIV/AIDS epidemics.
Explore the source record for details and available documents.
Acquired Immunodeficiency Syndrome↗
How well do antenatal clinic (ANC) attendees represent the general population? A comparison of HIV prevalence from ANC sentinel surveillance sites with a population-based survey of women aged 15-49 in Cambodia.
BACKGROUND: The purpose of this study was to evaluate whether HIV-1 prevalence among antenatal clinic (ANC) attendees in Cambodia provided a reasonable estimate of HIV-1 prevalence among all women 15-49 years. METHODS Antenatal clinic attendees in five HIV sentinel surveillance sites (five provinces) were selected by consecutive sampling (n = 1695). The population survey of females by household was carried out in the same five areas. Household females aged 15-49 years were selected using a three-stage cluster sampling design (n = 3066). Serum-based HIV ELISA testing was done for both ANC attendees and household females. The HIV prevalence for ANC attendees and household females were compared by age group and urban versus rural location. RESULTS: The overall prevalence of HIV-1 infection among ANC attendees (1.62%, 95% CI : 1.26-1.98) was similar to the overall prevalence obtained from the general population of household females (1.24%, 95% CI : 0.92-1.55) in the same catchment areas in Cambodia. In the rural areas, the overall HIV prevalence among ANC attendees (2.18%, 95% CI : 1.59-2.77) was significantly higher than among the household females (0.86%, 95% CI : 0.49-1.23) after adjustment for age distribution and education level. In the 15-24 age group in rural areas, the HIV prevalence of ANC women was 2.71% (95% CI : 0.96-4.46) compared with 0.77% (95% CI : 0.02-1.53) in household females. CONCLUSIONS: Although ANC data can be used to estimate trends over time, it should be realized that ANC data may overestimate the actual prevalence in the younger age group in rural areas in Cambodia.
Adolescent↗