Back to Annual Meeting Page		American Public Health Association 133rd Annual Meeting & Exposition December 10-14, 2005 Philadelphia, PA

Abstract #107846

Danielle C. Ompad, PhD, Shannon Blaney, MPH, Sarah Sisco, MPH, MSSW, David Vlahov, PhD, Sandro Galea, MD, MPH, DrPH, and for the VIVA Intervention Working Group of the Harlem Community and Academic Partnership. Center for Urban Epidemiologic Studies, New York Academy of Medicine, 1216 Fifth Avenue, New York, NY 10029, 212-419-3589, dompad@nyam.org

Objective: To enumerate hard-to-reach (HTR) populations (drug users, homeless, elderly shut-ins, immigrants) in 8 neighborhoods of East Harlem and the Bronx for a community-based influenza vaccine distribution study. Methods: Estimation of the number of HTR individuals in the 8 neighborhoods was performed using venue-based, door-to-door, and capture-recapture sampling techniques between January and August 2004. Results: When comparing the different enumeration methods, we found that: a) venue-based enumeration identified more middle-aged and economically-disadvantaged individuals, with more males, Hispanics (particularly Mexicans), homeless and uninsured ; 2) door-to-door enumeration identified a higher proportion of older people, women, Dominicans, Central Americans and African Americans; and 3) the capture-recapture method enumerated a higher proportion of young people, Puerto Ricans, West Indians/Caribbeans, and fewer uninsured and economically-disadvantaged individuals. Assuming a total population of 31,000 in target neighborhoods (per census data), door-to-door sampling techniques suggested that there were approximately 3,300 individuals Ан65 years old; 20,100 economically-disadvantaged individuals; 14,400 immigrants; 1,400 homeless; and 8,500 uninsured. There were approximately 4,000 non-injection drug users; 200 injection drug users and 1,200 HIV seropositive individuals in the neighborhoods. Conclusions: In a study to evaluate efforts to improve vaccination, denominators are needed with which to calculate vaccine rates. In the context of hidden populations, this represents a special challenge. The variety of estimates gathered by using different techniques provides a sense of the complexity in estimating counts of hidden populations. These techniques can supplement the Census in providing an estimate that likely includes those less likely to respond to an official census.

Learning Objectives: At the conclusion of the session, the participant (learner) in this session will be able to

• Describe three sampling techniques for the enumeration of hard-to-reach populations.
• Discuss the relative effectiveness of each technique for engaging different hard-to-reach populations.

Keywords: Methodology, Infectious Diseases

Presenting author's disclosure statement:

I wish to disclose that I have NO financial interests or other relationship with the manufactures of commercial products, suppliers of commercial services or commercial supporters.

Recorded presentation