Contact Us


» Chain Reports
» Consumer Focus Groups
» Community Profiles
» Epidemiology
» PE Initiatives
» Quality Management

The CHAIN Study

Click here to view Chain Reports

The Community Health Advisory & Information Network (CHAIN) is an ongoing prospective study of representative samples of persons living with HIV/AIDS in New York City and the Tri-County region of Westchester, Rockland and Putnam Counties. CHAIN is conducted by researchers from Mailman School of Public Health at Columbia University in collaboration with the New York City Department of Health and Mental Hygiene, Public Health Solutions, Inc. and the Westchester County Department of Health as part of evaluation activities of the New York Health and Human Services Planning Council. Its mission is to supply systematic data from the perspective of persons living with HIV about their needs for health and human services, their encounters with the full continuum of HIV services, and their physical, mental and social wellbeing.

Since its initiation in 1994, CHAIN has fielded three separate cohorts of persons living with HIV/AIDS. The first cohort was recruited between1994 and 1995 and remained active through 2001. A second NYC cohort was initiated in 2002 and remains active. Starting in 2001, CHAIN was extended to the Tri-County region. For all three cohorts, a two-stage sampling method was followed to recruit cohorts that would be representative of HIV positive adults (age 20+ years) who were aware of their HIV positive status. For the first stage, a large number of medical and social services known to have HIV case loads of 20 or more were invited to participate as recruitment sites. HIV positive clients were then recruited either through random selection from a client list prepared by agency staff or through onsite, sequential enrollment. For the 1994 NYC cohort, 648 HIV positive individuals were initially recruited from 43 of 52 sampled agencies. An additional 52 HIV positive individuals unconnected to medical care and case management services at the time of the interview were also recruited to supplement the agency-based sampling strategy. These "unconnected" individuals were contacted at outreach sites and through acquaintance sampling from among enrolled CHAIN participants. During 1998 an additional 286 HIV positive individuals were recruited from 22 of the 1994 recruitment sites. Baseline and up to seven follow-up interviews were completed with the members of this cohorts.

Following the same methodology used for the original CHAIN cohort, a new NYC CHAIN cohort was recruited between July 2002 and December 2003. A total of 684 HIV positive individuals were recruited from 36 agencies, along with nine persons living with HIV unconnected to care. During 2008 and 2009 we recruited an additional 319 HIV positive individuals. A baseline and six follow-up rounds of interviews have been completed with the 2002 NYC cohort. A seventh round of follow-up interviews was initiated in May 2013 and is scheduled for completing by the end of 2014.

A similar methodology was followed to recruit a Tri-County CHAIN cohort of 398 adults from 22 agencies during 2001 and 84 additional members between 2004 and 2006. Four rounds of interviews were completed by 2007. Starting in 2008 a repeated cross sectional design was instituted, in which unduplicated study participants are recruited over successive two-year cycles. Eighteen Tri-County agencies participate as recruitment sites. In this new procedure 125 to 150 HIV positive Tri-County residents are interviewed each year. Two two-year interview cycles have been completed. A third cycle was initiated during the winter of 2012 and is scheduled for completion during the winter of 2014. Although the current Tri-County sample is not longitudinal, a small number of individuals interviewed in one cycle are by chance re-interviewed in subsequent cycles.

Aside from death, sample attrition in the CHAIN cohorts has remained at low levels. Among CHAIN participants alive and still living in NYC, survey completion rates have remained in excess of 80 % and exceeded 90 percent for some rounds of individuals. Individuals lost to follow-up over the course of study showed few differences when compared with those who continued to participate.

CHAIN interviews, take approximately two hours to complete, and are conducted in person by trained community interviewers who were matched to respondents as much as possible with regard to gender and race/ethnicity. Approximately 10% of interviews are conducted in Spanish. Major interview topic areas include: (1) need for health and social services, (2) access, utilization and satisfaction with health and social services; (3) socio-demographic characteristics; (4) housing and other aspects of living situation; (5) sex and drug risk behaviors; (6) informal caregiving from friends, family and volunteers; and (7) their quality of life with respect to health status and psychological and social functioning. A number of items have been added over the years related to antiretroviral therapies, specific medical care services, care coordination, use of internet and social media and other topics of interest to policymakers, planners, providers, and members of the HIV Planning Council and its committees.

Each year CHAIN researchers produce a series of reports for the HIV Planning Council responding to the questions, interests, and priorities of the Council and its committees, the NYC Department of Health and Mental Hygiene (DOHMH), the Tri County Ryan White Part A Steering Committee and consumer communities. To date, close to 200 reports have been written examining a range of topics with focus on unmet health and social service needs, trends in service utilization and various outcomes among the CHAIN cohort. All CHAIN reports are available at no cost and widely distributed.

A Technical Review Team (TRT) provides oversight for the CHAIN Project in New York City and in the Tri-County. In addition to the research team from Columbia University's Mailman School of Public Health, TRT consists of representatives of NYC DOHMH, Public Health Solutions, and Westchester County Department of Health.

Since its inception the CHAIN project has been supported by the HIV Health and Human Services Planning Council of New York under a Part A (formerly Title I) grant from the Ryan White HIV Treatment Extension (formerly CARE) Act to the New York City Department of Health and Mental Hygiene. In addition to the work done on behalf of the Planning Council, CHAIN researchers have conducted special studies funded by the Ryan White SPNS program of the Health Resources and Services Administration (HRSA) HIV/AIDS Bureau, the Centers for Disease Control and Prevention, and most recently the MAC AIDS Foundation.

Below is a complete list of CHAIN documents since the study's inception in 1994. Reports that are electronically available are underlined with link to a pdf version of the document. Senior CHAIN investigators are available to present results from CHAIN studies to interested professional and community groups. For more information about Columbia University's Center for Applied Public Health, which produces the CHAIN reports, click here.

*You will need Adobe® Reader® to view these files.
Click HERE for a FREE download.