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Welcome to the Cancer Mortality Maps & Graphs Web site, provided by the National Cancer Institute (NCI) at the National Institutes of Health (NIH) . This site provides valuable information about cancer mortality in the U.S. during the time period 1950-1994, based on data obtained from the National Center for Health Statistics (NCHS), the Federal Government's principal vital and health statistics agency. On this site you will find several interactive data visualization tools to enhance your ability to view the data.

The Cancer Mortality Maps and Graphs Web site will be updated as new information becomes available. To facilitate future visits, please add this site http://www.nci.nih.gov/atlasplus/ to your list of bookmarks.

Frequently Asked Questions

What information is available on this Web site?

  • An online version of the Atlas of Cancer Mortality in the United States, 1950-94, which includes all the maps, tables, figures, and text included in the volume, as well as downloadable files of the data used to generate the maps.
  • Customizable mortality maps, which enable you to create U.S. cancer mortality maps by race and gender for various time periods for several age groups (and all ages combined) at the state, state economic area (SEA), or county level. You may choose to show the highest 1%, 5%, 10%, etc. of rates. You can also create multiple maps displaying geographic patterns using individual or common scales, and put those maps into motion.
  • Interactive mortality bar charts and trend line graphs, which allow you to view: (a) mortality rates and 95% confidence intervals by cancer by state, SEA, or county (sorted numerically or alphabetically); (b) 5-year rates over time for 1950-94 at the national, state, and SEA level; and (c) rates for various cancers at the national level, or state-by-state. (a) and (c) have the additional functionality to "drill down" from state to SEA or county.
  • Links to related U.S. and international sites, enabling you to supplement the information and data available on this Web site.

What is the purpose of this Web site?

The study of geographic patterns of cancer may provide important clues to the causes of cancer and improvements in cancer control. This site does not provide information about why death rates may be higher in certain localities than in others, but it can generate leads for in-depth epidemiologic studies that may shed light on factors contributing to cancer risks. Possible risk factors include tobacco use, occupational hazards, dietary habits, ethnic and socioeconomic background, and environmental exposures from the air or water. In addition, geographic variations in mortality rates may reflect differences in access to medical care, such as screening, diagnosis, or treatment.

Earlier cancer atlases published by NCI have made it possible for researchers to identify factors that contribute to the high rates of certain cancers in various parts of the country. Since a high proportion of cancers appear to be attributable to lifestyle and other environmental factors, it is hoped that many of the leads provided by this Web site and the associated Atlas will guide further epidemiologic and public health activities aimed at understanding and preventing cancer.

This Web site is a unique resource that should help researchers and health departments across the country to identify patterns of mortality at the county and SEA level, where the population is small enough to be relatively homogeneous, yet large enough to provide reliable data and stable rates. By using the county and SEA rates, it is possible to uncover patterns of cancer that have escaped notice when larger areas, such as states or regions, are evaluated. However, caution should be used when interpreting variations in rates based on small numbers. Confidence intervals (95%) likely contain the true value of the rate and are presented in the bar charts and downloadable data files.

What data are included on the Web site?

Death rates are presented by race and gender for the following time periods, 1950-94, 1950-69, 1970-94, and the nine 5-year time periods from 1950-54 through 1990-94. Rates are available for all ages combined, and for the age groups 0-19, 20-49, 50-74, 75+. Rates are calculated for all cancers combined and for approximately 40 cancers separately. Maps and graphs are presented at the level of county (3,055), state economic area (SEA) (508), and state (50 + the District of Columbia). (SEAs consist of individual counties or groups of counties within a state with similar economic and cultural characteristics).

Mortality data are not available for all races because there are few annual population estimates on a county level for nonwhites other than blacks. Mortality data for whites are available for the entire time period, 1950-94, whereas data for blacks are available only from 1970 onward. Data are not available specifically for Asians, Hispanics, or Native Americans.

The entire contents of the volume, Atlas of Cancer Mortality in the United States, 1950-94, are available on the Web site. Downloadable tabulated data used to generate the atlas maps are also available.

What are some principles that are important to keep in mind when interpreting the maps and graphs on this Web site?

  • The maps can identify high-risk areas of the country where hypothesis-testing epidemiologic studies may be targeted, but the maps by themselves cannot identify the causes of cancer.

  • Rates may be significantly elevated in some geographic units due to chance.

  • Consistently high rates for a specific form of cancer in several neighboring counties or SEAs may indicate an area where a high frequency of individuals are exposed to a particular lifestyle or other environmental risk factor for this cancer.

  • Individuals in areas with consistently low rates may have a low frequency of risk factors and/or a high frequency of protective factors.

  • Geographic pointers for future research are less apparent for cancers with limited variation across the country.

  • For cancers with poor survival rates, mortality data closely reflect incidence data. These patterns are particularly useful for geographic areas where no population-based incidence data are available, and for cancers whose incidence rates are strongly influenced by variations in diagnostic practice.

  • For cancers with higher survival rates, the geographic variations in mortality may reflect not only environmental risk factors, but also differences in medical care and healthcare delivery systems.

  • It is not possible to evaluate the effect that moving from one part of the country to another has on the death rates, because only the usual residence at time of death is recorded on death certificates.

Does the atlas provide information about cancer clusters?

No. A "cancer cluster" is generally defined as the occurrence of a greater than expected number of cancer cases or deaths over a short period of time in a small area, such as a neighborhood, a workplace, or medical practice. In such instances, the Atlas or Web site may be helpful in providing background information about how cancer mortality rates in a particular county or SEA compare to the surrounding counties or SEAs, or to the state or national rates, but it cannot provide information at the level of town or neighborhood. In the context of the Atlas, a "geographic cluster" is used to indicate a group of adjacent counties or SEAs with unusually high rates compared to other parts of the country. Click here for more information on cancer clusters.