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Geographic Information Systems (GIS) Overview of GIS and Cancer What is
GIS? Why use GIS? FAQs Cancer Atlas Our Model GIS Atlas Atlas
Geographic Information Systems (GIS)
Overview of GIS and Cancer Since the first use of a geographic system to
assess the location of childhood leukemia [Openshaw et al, 1987], GIS
applications have been developed, utilized and continuously refined for the
mapping and spatial analysis of cancer incidence, morbidity and mortality
data. Four general approaches for utilizing GIS in cancer research have been
taken: 1) disease mapping; 2) geographic correlation studies; 3) risk
assessment in relation to a pre-specified point or line source; and 4)
cluster detection and disease clustering [Wakefield & Elliott, 1999].
The National Cancer Institute (NCI) provides funding and maintenance
support for GIS-related cancer research. A major initiative of NCI has been
the development of a prototype GIS, the Geographic Information System for
Health (GIS-H), as part of the Long Island Breast Cancer Study Project
[National Cancer Institute, 2003]. GIS-H is a web-based resource and provides
a broad and growing body of data to public and individual researchers, in
addition to statistical and GIS tools to facilitate research. The GIS-H can
be used to study various types of cancer and conditions. In a second major
initiative, the NCI awarded 12 grants in Fiscal Years 2001 and 2002 on
Geographic-based Research in Cancer Control and Epidemiology. These projects
include investigations of the determinants of geographic patterns of cancer
uncovered by the Atlas of Cancer Mortality in the United States, 1950-1994;
geographic information systems; and methodological research to advance the
use of GIS in understanding cancer etiology, including geovisualization and
spatial analysis of cancer data study by the submitting investigators [MacEachren
et al, 2003].
Recently, the North American Association of Central Cancer Registries (NAACCR)
has been developing a GIS handbook for central cancer registries. The
handbook is expected to be released in July 2003 and will serve as a guide
for registries as they choose to employ GIS.
What is GIS?
GIS.com has a nice, brief overview of GIS: http://www.gis.com/whatisgis/index.html
US Geological Survey provides a more detailed explanation: http://erg.usgs.gov/isb/pubs/gis_poster/
Why use GIS?
GIS.com has short article with examples: http://www.gis.com/whatisgis/whyusegis.html
FAQs: Maybe Alan and David could write??
Cancer Atlas-Background
Previously developed atlases of georeferenced health statistics have, in
the past, led to insights concerning various health-environment-behavior
interactions [Mason et al, 1975; Pickle et al, 1987; Pickle et al, 1990;
Pickle et al, 1997; Devesa et al, 1999aMason, 1995]. Spatial associations
identified have prompted hypotheses about the causal relations, some of which
have been verified [Devesa et al, 1999]. Examples specifically related to
cancer include identification of "hot spots” of esophageal cancer in China
and oral cancer in the U.S. state of North Carolina [Winn et al, 1981].
Devesa and colleagues [Devesa et al, 1999a], in one of the most recent
printed cancer atlases, cite a wide range of findings about cancer derived by
correlation and field studies that were stimulated by the publication of
previous atlases. They note, for example, that maps lead to studies
indicating that “some evidence that farming and agricultural exposures may
contribute to the geographic variation in prostate cancer, including high
rates among whites in north central and northwestern areas, and among blacks
in parts of the Southeast” and that “high colon cancer death rates in eastern
Nebraska are linked to persons of Czechoslovakian background, and nutritional
factors appear to contribute to the elevated risk”.
NCI has produced six cancer mortality atlases since 1975. More recently,
NCI has begun to disseminate maps, graphs, and other cancer statistics over
the web with an online version of the most recent cancer atlas
(http://www3.cancer.gov/atlasplus/). NCI recently launched Cancer Control
PLANET (http://cancercontrolplanet.cancer.gov/) as a portal to the five steps
in Comprehensive Cancer Control planning for state health departments.
However, the initial launch of PLANET limited its use of GIS/Atlas methods.
Drs. B. Sue Bell and Linda Pickle, members of our advisory committee, have
been instrumental in NCI’s various efforts to analyze, interpret, and present
geotemporal cancer data.
Our Model GIS Atlas
The power of GIS for comprehensive cancer control, however, comes from the
flexibility and extensibility of the digital environment. A digital,
GIS-based Atlas has the potential to combine the ability of paper maps to
prompt insight about spatial distributions and relationships with the ability
of the digital environment to support exploratory analysis, hypothesis
generation, statistical and computational testing of hypotheses, policy
decision making, and dissemination of information in a variety of forms (many
of which retain the dynamic characteristics of the underlying GIS).
The product we propose will integrate new data continuously and produce
new outputs to meet particular needs. It will also provide a framework for
extending the GIS functionality over time. We propose a series of research,
development, and implementation tasks within this aim that will allow the
development of an integrated, dynamic, extensible GIS-based Atlas. These
tasks address aspects of: data compilation and transformation, map design and
dynamic visualization, interface use and usability, developing spatial
analysis methods, and extending spatial analysis capabilities of GIS.
Finally, we propose to test the products and methods through both
dissemination and to complete two case studies in hypothesis-generated
epidemiological research on colorectal and prostate cancer.
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