Use of density equalizing map projections (DEMP) in the analysis of childhood cancer in four California counties
- Lawrence Berkeley Lab., CA (United States). Information and Computing Sciences Div.
In studying geographic disease distributions, one normally compares rates of arbitrarily defined geographic subareas (e.g. census tracts), thereby sacrificing the geographic detail of the original data. The sparser the data, the larger the subareas must be in order to calculate stable rates. This dilemma is avoided with the technique of Density Equalizing Map Projections (DEMP). Boundaries of geographic subregions are adjusted to equalize population density over the entire study area. Case locations plotted on the transformed map should have a uniform distribution if the underlying disease-rates are constant. On the transformed map, the statistical analysis of the observed distribution is greatly simplified. Even for sparse distributions, the statistical significance of a supposed disease cluster can be reliably calculated. The present report describes the first successful application of the DEMP technique to a sizeable ``real-world`` data set of epidemiologic interest. An improved DEMP algorithm [GUSE93, CLOS94] was applied to a data set previously analyzed with conventional techniques [SATA90, REYN91]. The results from the DEMP analysis and a conventional analysis are compared.
- Research Organization:
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- AC03-76SF00098
- OSTI ID:
- 10117532
- Report Number(s):
- LBL-36630; CONF-950168-1; ON: DE95006573; TRN: AHC29509%%74
- Resource Relation:
- Conference: 1995 CDC/ATSDR symposium on statistical methods: small area statistics in public health: design, analysis graphic and spatial methods,Atlanta, GA (United States),25-26 Jan 1995; Other Information: PBD: Jan 1995
- Country of Publication:
- United States
- Language:
- English
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