International Journal of Health Geographics | 2010
Authors:
DOI: 10.1186/1476-072X-9-10
Journal: International Journal of Health Geographics
Year: 2010
Publisher:
Document Type: Article
Open Access: All Open Access; Gold Open Access; Green Open Access
Cited by: 31
Background: Automated geocoding of patient addresses for the purpose of conducting spatial epidemiologic studies results in positional errors. It is well documented that errors tend to be larger in rural areas than in cities, but possible effects of local characteristics of the street network, such as street intersection density and street length, on errors have not yet been documented. Our study quantifies effects of these local street network characteristics on the means and the entire probability distributions of positional errors, using regression methods and tolerance intervals/regions, for more than 6000 geocoded patient addresses from an Iowa county.Results: Positional errors were determined for 6376 addresses in Carroll County, Iowa, as the vector difference between each 100%-matched automated geocode and its ground-truthed location. Mean positional error magnitude was inversely related to proximate street intersection density. This effect was statistically significant for both rural and municipal addresses, but more so for the former. Also, the effect of street segment length on geocoding accuracy was statistically significant for municipal, but not rural, addresses; for municipal addresses mean error magnitude increased with length.Conclusion: Local street network characteristics may have statistically significant effects on geocoding accuracy in some places, but not others. Even in those locales where their effects are statistically significant, street network characteristics may explain a relatively small portion of the variability among geocoding errors. It appears that additional factors besides rurality and local street network characteristics affect accuracy in general. © 2010 Zimmerman and Li; licensee BioMed Central Ltd.
Bias (Epidemiology); Cluster Analysis; Epidemiologic Research Design; Geographic Information Systems; Humans; Iowa; Residence Characteristics; Rural Population; epidemiology; error analysis; information system; probability; public health; article; cluster analysis; demography; epidemiology; geographic information system; human; rural population; standard; United States