Title: Assessing uncertainty in spatial exposure models for air pollution health effects assessment.
Authors: Molitor, John; Jerrett, Michael; Chang, Chih-Chieh; Molitor, Nuoo-Ting; Gauderman, Jim; Berhane, Kiros; McConnell, Rob; Lurmann, Fred; Wu, Jun; Winer, Arthur; Thomas, Duncan
Published In Environ Health Perspect, (2007 Aug)
Abstract: BACKGROUND: Although numerous epidemiologic studies now use models of intraurban exposure, there has been little systematic evaluation of the performance of different models. OBJECTIVES: In this present article we proposed a modeling framework for assessing exposure model performance and the role of spatial autocorrelation in the estimation of health effects. METHODS: We obtained data from an exposure measurement substudy of subjects from the Southern California Children's Health Study. We examined how the addition of spatial correlations to a previously described unified exposure and health outcome modeling framework affects estimates of exposure-response relationships using the substudy data. The methods proposed build upon the previous work, which developed measurement-error techniques to estimate long-term nitrogen dioxide exposure and its effect on lung function in children. In this present article, we further develop these methods by introducing between- and within-community spatial autocorrelation error terms to evaluate effects of air pollution on forced vital capacity. The analytical methods developed are set in a Bayesian framework where multistage models are fitted jointly, properly incorporating parameter estimation uncertainty at all levels of the modeling process. RESULTS: Results suggest that the inclusion of residual spatial error terms improves the prediction of adverse health effects. These findings also demonstrate how residual spatial error may be used as a diagnostic for comparing exposure model performance.
PubMed ID: 17687440
MeSH Terms: Adolescent; Air Pollutants/analysis*; Air Pollutants/toxicity; Air Pollution/adverse effects; Air Pollution/analysis*; Bayes Theorem; California/epidemiology; Child; Environmental Monitoring/statistics & numerical data*; Humans; Lung Diseases/epidemiology; Lung Diseases/etiology; Models, Biological*; Nitrogen Dioxide/analysis*; Nitrogen Dioxide/toxicity; Uncertainty; Vehicle Emissions/toxicity; Vital Capacity/drug effects