Title: | "Sampling design, response rates, and analysis weights for the National Human Exposure Assessment Survey (NHEXAS) in EPA region 5" |
Author(s): | Whitmore RW; Byron MZ; Clayton CA; Thomas KW; Zelon HS; Pellizzari ED; Lioy PJ; Quackenboss JJ; |
Address: | "Research Triangle Institute, Research Triangle Park, NC 27709-2194, USA. rww@rti.org" |
Journal Title: | J Expo Anal Environ Epidemiol |
ISSN/ISBN: | 1053-4245 (Print) 1053-4245 (Linking) |
Abstract: | "For the Phase I field test of the National Human Exposure Assessment Survey (NHEXAS) in U.S. Environmental Protection Agency (EPA) Region 5, this paper presents the survey sampling design, the response rates achieved, and the sample weighting procedure implemented to compensate for unit nonresponse. To enable statistically defensible inferences to the entire region, a sample of about 250 members of the household population in EPA Region 5 was selected using a stratified multistage probability-based survey sampling design. Sample selection proceeded in four nested stages: (1) sample counties; (2) area segments based on Census blocks within sample counties; (3) housing units (HUs) within sample segments; and (4) individual participants within sample households. Each fourth-stage sample member was asked to participate in 6 days of exposure monitoring. A subsample of participants was asked to participate in two rounds of longitudinal follow-up data collection. Approximately 70% of all sample households participated in household screening interviews in which rosters of household members were developed. Over 70% of the sample subjects selected from these households completed the Baseline Questionnaire regarding their demographic characteristics and potential for exposures. And, over 75% of these sample members went on to complete at least the core environmental monitoring, including personal exposures to volatile organic compounds (VOCs) and tap water concentrations of metals. The sample weighting procedures used the data collected in the screening interviews for all household members to fit logistic models for nonresponse in the later phases of the study. Moreover, the statistical analysis weights were poststratified to 1994 State population projections obtained from the Bureau of the Census to ensure consistency with other statistics for the Region" |
Keywords: | "Adolescent Adult Aged Child Child, Preschool Data Collection/*methods Environmental Monitoring/*methods Female Follow-Up Studies Great Lakes Region Humans Infant Logistic Models Male Middle Aged *Research Design Seasons;" |
Notes: | "MedlineWhitmore, R W Byron, M Z Clayton, C A Thomas, K W Zelon, H S Pellizzari, E D Lioy, P J Quackenboss, J J eng Research Support, U.S. Gov't, Non-P.H.S. England 1999/11/30 J Expo Anal Environ Epidemiol. 1999 Sep-Oct; 9(5):369-80. doi: 10.1038/sj.jea.7500054" |