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About This Site

The About This Site section provides information on the purpose, history, and development of as well as help with using the information found on the site. Background

Find out about the site's purpose. Learn about the information available on, who supplies it, and how you can use it.

About the Results Database

Learn about the summary results information available in a standard, tabular format on

History, Policies, and Laws

Learn about the events, policies, and laws that affected the creation, development, and expansion of

Media/Press Resources

Find background information and statistics about the site specifically for members of the press.

Linking to This Site

Learn how to link to major access points of the site, such as search results, study records, and the home page.

Terms and Conditions

Read the statement on the availability and appropriate use of information on the site.


Read the disclaimer regarding information on the site.

This page last reviewed in November 2015