HIV Open Data Project: National HIV Behavioral Surveillance System: Eligibility Screener and Core Questionnaire

In 2003, CDC created the National HIV Behavioral Surveillance System (NHBS) for conducting behavioral surveillance among persons at high risk for HIV infection. Surveillance is conducted in rotating annual cycles in three different populations at high risk for HIV: men who have sex with men (MSM), injection drug users (IDUs), and heterosexuals at increased risk for HIV infection (HET). Before each NHBS cycle, formative research is conducted to learn more about the populations and collect data to help with sampling procedures. MSM are sampled using venue-based, time-space sampling methods. Health department staff members first identify venues frequented by MSM (e.g., bars, clubs, organizations, and street locations) and days and times when men frequent those venues. Venues (and specific day/time periods) for recruitment are chosen randomly each month. IDUs and heterosexuals are recruited using respondent-driven sampling, a type of chain referral sampling. Health department staff members select a small number of initial participants, or "seeds," who complete the survey and recruit their peers to participate. Recruitment and interviewing continue until the target sample size is reached. Trained interviewers in all NHBS jurisdictions use a standardized anonymous questionnaire to collect information on HIV-related risk behaviors, HIV testing, and use of HIV prevention services. HIV testing is also offered to all participants. During each cycle, a minimum of 450 (for heterosexuals) to 500 (for MSM and IDUs) eligible persons from each participating jurisdiction are interviewed and tested for HIV infection. The first full round of NHBS, comprised all three cycles (MSM, IDU, and HET), was conducted during 2003-2007. The second round was conducted during 2008-2010, and the third round began in January 2011. As of 2011, 20 jurisdictions with high AIDS prevalence are funded to conduct NHBS. Many of the health department grantees subcontract with local health departments, universities, or community-based organizations to implement NHBS activities. Data on behavioral risks for HIV, HIV testing behaviors, access to and use of prevention services and HIV testing results are collected. NHBS data are used to provide a behavioral context for trends seen in HIV surveillance data. They also describe populations at increased risk for HIV infection and thus provide an indication of the leading edge of the epidemic. Through systematic surveillance in groups at high risk for HIV infection, NHBS will be critical for monitoring the impact of the National HIV/AIDS Strategy, which focuses on decreasing HIV incidence, improving linkage to care, and reducing disparities.

2003年，美国疾病控制与预防中心（Centers for Disease Control and Prevention，CDC）创建了全国艾滋病病毒行为监测系统（National HIV Behavioral Surveillance System，NHBS），用于针对艾滋病病毒（HIV）感染高风险人群开展行为监测。监测以年度轮换周期实施，覆盖三类HIV高风险人群：男男性行为者（men who have sex with men，MSM）、注射毒品使用者（injection drug users，IDUs）以及HIV感染风险升高的异性恋者（heterosexuals at increased risk for HIV infection，HET）。每一轮NHBS启动前，均会开展形成性研究（formative research），以深入摸排目标人群特征并收集数据，辅助优化抽样流程。男男性行为者采用基于场所的时空抽样方法招募：疾控人员首先确定男男性行为者常光顾的场所（如酒吧、俱乐部、社会组织及街头点位），以及该群体到访各场所的具体日期与时段，每月随机选定招募场所及对应时段。注射毒品使用者与高风险异性恋者则采用受访者驱动抽样法（respondent-driven sampling，一种链式推荐抽样方法）进行招募：疾控人员先选取少量初始参与者，即“种子（seeds）”，待其完成问卷调研后，由其招募同伴参与，直至达成目标样本量。所有NHBS覆盖地区的经培训访员，均采用标准化匿名问卷收集与HIV相关的风险行为、HIV检测及艾滋病预防服务使用情况等信息，同时为所有参与者提供HIV检测服务。每一轮监测周期中，每个参与地区需完成至少450名符合条件的高风险异性恋者，以及500名男男性行为者和注射毒品使用者的访谈与HIV检测。首轮NHBS覆盖全部三类人群（MSM、IDU及HET），于2003-2007年开展；第二轮监测于2008-2010年实施，第三轮则于2011年1月启动。截至2011年，全美共有20个艾滋病高流行地区获得资助开展NHBS。多数疾控项目受资助方会与地方疾控部门、高校或社区组织签订分包合同，以落实NHBS各项活动。本次监测收集的数据涵盖HIV行为风险因素、HIV检测行为、预防服务的可及性与使用情况，以及HIV检测结果。NHBS数据可为艾滋病监测数据中呈现的流行趋势提供行为学背景，同时可刻画HIV感染高风险人群的特征，进而指示艾滋病疫情的前沿态势。通过针对HIV高风险人群开展系统性监测，全国艾滋病病毒行为监测系统将为评估《国家艾滋病战略》（National HIV/AIDS Strategy）的实施成效提供关键支撑——该战略旨在降低HIV新发感染率、优化感染者的诊疗衔接工作，并缩小健康差距。