Atlas of Cancer Mortality
Materials and Methods -- Map Production
Maps displaying cancer mortality rates by county and SEA were
produced using Atlas Pro and Atlas GIS for Windows software
(Strategic Mapping, Inc., now part of ESRI) on a Pentium personal
computer. For ease of comparisons and readability, the size of
Alaska was reduced and, for the SEA maps, the size of the District
of Columbia was increased and separated from adjacent areas. Prior
to mapping, rates for an area based on sparse data were deemed
unstable if (a) the observed number of deaths was less than 6; (b)
the observed number of deaths was less than 12 and the rate was not
significantly different statistically from the U.S. rate; or (c) the
expected number of deaths was less than 6 and the rate was not
significantly different statistically from the U.S. rate. The stable
rates were then ranked and partitioned into 10 deciles. The legend
for each map portrays the national rate and the range of rates for
each decile. Rates per 100,000 person-years are generally presented
with 2 digits to the right of the decimal, although for some of the
rarer cancers 3 digits are shown. In each map and legend, five
shades of red (deciles at the median and above) and five shades of
blue (deciles below the median) are used, with the intensity of
color reflecting the ranked distance from the median. Gray is used
for areas with sparse data (i.e., unstable rates as defined above).
Suggested Citation
Devesa SS, Grauman DG, Blot WJ, Pennello G, Hoover RN, Fraumeni JF Jr. Atlas of cancer
mortality in the United States, 1950-94. Washington, DC: US Govt Print Off; 1999 [NIH Publ No.
(NIH) 99-4564].
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