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.
Tammemagi CM, Neslund-Dudas C, Simoff M, Kvale P.Tammemagi CM, et al. Among authors: kvale p.Chest. 2004 Jan;125(1):27-37. doi: 10.1378/chest.125.1.27.Chest. 2004.PMID: 14718417