Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Ten most common search strategies, January 1, 2009-December 31, 2009*
* The 100 most commonly used search terms and phrases during the study period were reviewed and grouped by general topic. The top ten general topics are listed in this Figure.
