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.
Goldman SE, Stone KL, Ancoli-Israel S, Blackwell T, Ewing SK, Boudreau R, Cauley JA, Hall M, Matthews KA, Newman AB.Goldman SE, et al. Among authors: matthews ka.Sleep. 2007 Oct;30(10):1317-24. doi: 10.1093/sleep/30.10.1317.Sleep. 2007.PMID: 17969465Free PMC article.