Landscape-epidemiological study design to investigate an environmentally based disease
Joseph A Tabor1, Mary Kay O'rourke, Michael D Lebowitz
1Office of Arid Lands Studies, College of Agriculture and Life Sciences, The University of Arizona, Tucson, Arizona 85721, USA. jatabor@u.arizona.edu
Journal of Exposure Science & Environmental Epidemiology
|March 4, 2010
Summary
This study shows that clustered, address-based telephone surveys are a cost-effective way to recruit participants for epidemiological studies. Using geographic information systems (GIS) and landscape ecology improves sampling efficiency for environmental risk factor analysis.
Area of Science:
- Epidemiology
- Geographic Information Systems (GIS)
- Landscape Ecology
Background:
- Community-based epidemiological studies face challenges in subject identification and enrollment, particularly at the neighborhood scale for environmental risk factors.
- Distinguishing between individual- and group-level risk factors requires analysis at a neighborhood scale, posing additional methodological hurdles.
Purpose of the Study:
- To evaluate the cost-effectiveness and validity of a stratified, address-based telephone survey method for subject recruitment in epidemiological research.
- To assess the utility of geographic information systems (GIS) in neighborhood-scale sampling and the impact of stratification on survey design effect.
- To determine the most robust demographic factors for post-stratification to correct for selection bias.
Main Methods:
- A stratified, two-stage, cross-sectional, address-based telephone survey was conducted in Greater Tucson, Arizona (2002-2003).
- Subjects were recruited using direct marketing data at neighborhood resolution via GIS, with households randomly selected within census block groups.
- Landscape ecology principles were used for stratification, and post-stratification adjustments were made using race-ethnicity, age, and gender.
Main Results:
- The survey achieved a cost-effective recruitment of participants using address-based lists and GIS.
- The survey design effect for coccidioidomycosis prevalence was substantially reduced in several strata.
- Race-ethnicity proved more effective than age and gender in compensating for selection bias through post-stratification.
Conclusions:
- Clustered, address-based telephone surveys are a valid and cost-effective method for population recruitment in epidemiological studies.
- Integrating GIS for survey design and employing appropriate statistical methods enhances analysis of environmental determinants.
- Landscape ecology approaches improve sampling efficiency for studies investigating environmental risk factors.
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