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.
Sobolev BG, Levy AR, Kuramoto L, Hayden R.Sobolev BG, et al. Among authors: levy ar.BMC Health Serv Res. 2005 Sep 26;5:63. doi: 10.1186/1472-6963-5-63.BMC Health Serv Res. 2005.PMID: 16185357Free PMC article.