title: Spatializing Area-Based Measures of Neighborhood Characteristics for Multilevel Regression Analyses: An Areal Median Filtering Approach.
abstract: Area-based measures of neighborhood characteristics simply derived from enumeration units (e.g., census tracts or block groups) ignore the potential of spatial spillover effects, and thus incorporating such measures into multilevel regression models may underestimate the neighborhood effects on health. To overcome this limitation, we describe the concept and method of areal median filtering to spatialize area-based measures of neighborhood characteristics for multilevel regression analyses. The areal median filtering approach provides a means to specify or formulate "neighborhoods" as meaningful geographic entities by removing enumeration unit boundaries as the absolute barriers and by pooling information from the neighboring enumeration units. This spatializing process takes into account for the potential of spatial spillover effects and also converts aspatial measures of neighborhood characteristics into spatial measures. From a conceptual and methodological standpoint, incorporating the derived spatial measures into multilevel regression analyses allows us to more accurately examine the relationships between neighborhood characteristics and health. To promote and set the stage for informative research in the future, we provide a few important conceptual and methodological remarks, and discuss possible applications, inherent limitations, and practical solutions for using the areal median filtering approach in the study of neighborhood effects on health.
authors.affiliation: Social and Cardiovascular Epidemiology Research Group, Faculty of Medicine, University of Alcalá, Campus Universitario - Ctra. Madrid-Barcelona, Km 33,6000, 28871, Alcalá de Henares, Madrid, Spain. moka@post.harvard.edu.
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Oka
authors.affiliation: Department of Geography and GeoInformation Science, College of Science, George Mason University, Fairfax, VA, USA.
authors.forename: David W S
authors.initials: DW
authors.lastname: Wong
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D008875:Middle Aged; D012044:Regression Analysis; D012111:Residence Characteristics / Q000706:statistics & numerical data; D062206:Spatial Analysis; D014481:United States
keywords: Area-based measures; Areal data; Median filter; Multilevel regression analysis; Spatial approach; Spatial median; USA