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.
Roig M, Reid WD.Roig M, et al. Among authors: reid wd.Respir Med. 2009 Apr;103(4):485-95. doi: 10.1016/j.rmed.2008.11.008. Epub 2008 Dec 16.Respir Med. 2009.PMID: 19091537Free article.Review.