An official website of the United States government
The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before
sharing sensitive information, make sure you’re on a federal
government site.
The site is secure.
The https:// ensures that you are connecting to the
official website and that any information you provide is encrypted
and transmitted securely.
Arillo-Santillan E, Lazcano-Ponce E, Hernandez-Avila M, Fernández E, Allen B, Valdes R, Samet J.Arillo-Santillan E, et al.Am J Prev Med. 2005 Jan;28(1):41-51. doi: 10.1016/j.amepre.2004.09.002.Am J Prev Med. 2005.PMID: 15626554