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.
Trauner DA, Mannino F.Trauner DA, et al.Lancet. 1996 Jun 15;347(9016):1701. doi: 10.1016/s0140-6736(96)91535-4.Lancet. 1996.PMID: 8642996No abstract available.