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.
Kolle E, Steene-Johannessen J, Holme I, Andersen LB, Anderssen SA.Kolle E, et al.BMC Public Health. 2009 Oct 14;9:389. doi: 10.1186/1471-2458-9-389.BMC Public Health. 2009.PMID: 19828037Free PMC article.