Back to Annual Meeting Page		American Public Health Association 133rd Annual Meeting & Exposition December 10-14, 2005 Philadelphia, PA

Abstract #115575

Tim Gallagher, RS, Epidemiology and Surveillance, Cuyahoga County Board of Health, 5550 Venture Dr., Parma, OH 44130, 216-201-2001 ext 1614, tgallagher@ccbh.net

Background: The lack of standardized street level address information captured in reportable disease reports makes rapid geocoding of cases difficult. A spatial layer composed of polygons from the intersection of zip codes with a municipality layer and processed with attribute data of census blocks could serve as a familiar level of geography to stratify data, calculate incidence rates and display data.

Objective: Develop a GIS layer at a level of geography that provides reliable denominator data for rapid epidemiologic and spatial analysis using address information which is uniformly collected during disease reporting and is compatible with syndromic disease data aggregated at the zip code level.

Methods: A layer was created by merging Consolidated Subdivisions and Census 2000 ZCTAs™ (ZIP Code Tabulation Areas) layers for Cuyahoga County, Ohio. Validation of this layer uncovered severe discrepancies which require this analysis be performed again with another source of Zip Code data. A partitioning algorithm will be applied to the muni-zip layer to calculate area-weighted demographics of 2000 Census Block polygons.

Results: Geoprocessing using ZCTAs™ produced more than twice the valid number of muni-zip polygons. While ZCTAs™ are approximations of actual mailing ZIP Codes, TIGER/Line® files contain address ranges with actual mailing USPS ZIP Codes. The effectiveness of analysis using TIGER files is under evaluation.

Conclusion: Geographic preprocessing can generate data for spatial analysis by applications without robust geocoding capabilities.

Learning Objectives: "At the conclusion of this session, the participant will be able to

• Compare and contrast the requirements of street level and muni-zip level geocoding."
• Identify three advantages of mun-zip geographic preprocessing."
• Describe the differences between Zip Code Tabulation Areas and United States Postal Service Zip Codes."

Keywords: Data/Surveillance, Geographic Information Systems

Presenting author's disclosure statement:

I wish to disclose that I have NO financial interests or other relationship with the manufactures of commercial products, suppliers of commercial services or commercial supporters.