An individual’s health is affected by one’s “spatial context,” that is, where one lives. Spatial context is characterized by 3 domains that influence health through local exposures, risks, and available care:

• Specific geographic/environmental conditions, particularly, the quality of the air, water, and food supply
• Neighborhood characteristics that influence lifestyle and stress, such as crime, easy access to exercise, access to tobacco, alcohol, and illicit drugs
• Health services, such as available clinics, hospitals, and appropriate numbers of primary care and specialist health professionals

The National Cancer Institute (NCI) is investigating how spatial context affects cancer risk and asked Westat to contribute its geographic information system (GIS) expertise to the effort.

Westat is currently working directly with individual state cancer registries and coordinating with NCI in collaboration with the North American Association of Central Cancer Registries (NAACCR) on the NCI/NAACCR Zone Design Project. The project aims to develop a set of cancer reporting zones across the U.S. that are more suitable for cancer data reporting than counties.

We are assisting in building residential histories using commercial vendor data linked to SEER patients for the purposes of enhancing data linkages between SEER and other data sources (e.g., pharmacy data) and to facilitate research, including environmental exposure studies. Westat conducted a pilot study to determine the best available commercial vendor data to use for the data linkage, and to develop algorithms to build residential histories from raw address data. Westat is currently working on enhancing the algorithms that will help build residential histories for all linked SEER patients.

We are providing recommendations on developing GIS web mapping tools, including tools for choosing mapping schemes, classifying cancer rates, and choosing variables to be mapped. In addition, Westat works with NCI to develop map stories, which use narrative and map-based explanations to explore various cancer-related topics.

We provided recommendations on the redesign of NCI's "Geographic Information Systems and Science for Cancer Control" website and continue to provide guidance for updates to the website. The site is a central source of information about GIS and related resources for use by the public, cancer researchers, and the media. Westat’s recommendations will include site content organization and placement, graphic design, and maintenance and updates.

Westat’s contributions to the SEER program will help establish a GIS specialty infrastructure to continue investigations into spatial context and cancer risk.