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.
Abraham AG, Kulp-Shorten CL, Callen JP.Abraham AG, et al. Among authors: callen jp.South Med J. 1998 Apr;91(4):349-53. doi: 10.1097/00007611-199804000-00007.South Med J. 1998.PMID: 9563426
Schrodt BJ, Kulp-Shorten CL, Callen JP.Schrodt BJ, et al. Among authors: callen jp.South Med J. 1999 May;92(5):502-4. doi: 10.1097/00007611-199905000-00010.South Med J. 1999.PMID: 10342897