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Brain cancer mortality in the United States, 1986 to 1995: A geographic
analysis
Zixing Fang, Martin Kulldorff, And David I. Gregorio
Department of Human Genetics, University
of California Los Angeles School of Medicine, Los Angeles, CA 90095-7088 (Z.F.);
Department of Ambulatory Care and Prevention, Harvard Medical School and Harvard
Pilgrim Health Care, Boston, MA 02215 (M.K.); Department of Community Medicine
and Health Care, University of Connecticut School of Medicine, Farmington, CT
06030-6325 (D.I.G.); USA.
The Atlas of Cancer Mortality in the United States, 1950-94 (Devesa et
al.) published in 1999 by the National Institutes of Health suggests that there
are elevated rates of brain and other nervous system cancer in the northwestern,
north central, and southeastern parts of the country.
Being descriptive in nature, the atlas does not evaluate whether observed
patterns are simply due to random variation or if they are reflective of true
geographical differences in disease risk or treatment practices.
To formally test for geographical clustering of disease, we analyzed U. S. brain
cancer mortality data from 1986 to 1995 with Tango's Excess Events test, the
Cuzick-Edwards k-Nearest-Neighbors test, and the spatial scan statistic.
All tests revealed statistically significant geographical clustering for both
adult men and women.
The spatial scan statistic indicated that the most likely cluster of high
mortality was in parts of Arkansas, Mississippi, and Oklahoma (relative risk
[RR] = 1.22, P 0.0001) for women and in parts of Tennessee and Kentucky
(RR = 1.15, P < 0.0001) for men.
Several secondary clusters were detected, but there were no statistically
significant clusters of a very localized nature and a high RR.
For childhood brain cancer, there were no statistically significant geographical
clusters.
It is reassuring that no local brain cancer mortality "hot spots" with
very high RRs were found.
While the causes of the large geographical clusters with modest RRs are unclear,
the geographical pattern of brain cancer mortality provides valuable information
that can help in formulating etiological hypotheses and in targeting high-risk
populations for further epidemiological and health services research.
© 2004 Duke University Press
Source: http://lysander.ingentaselect.com/vl=19350360/cl=25/nw=1/rpsv/cgi-bin/linker?ini=dup_no&reqidx=/cw/dup/15228517/v6n3/s1/p179
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