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.
Chang JC, Cohen RD.Chang JC, et al. Among authors: cohen rd.Gastroenterol Clin North Am. 2004 Jun;33(2):235-50, viii. doi: 10.1016/j.gtc.2004.02.005.Gastroenterol Clin North Am. 2004.PMID: 15177536Review.