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.
Clark CR, Ridker PM, Ommerborn MJ, Huisingh CE, Coull B, Buring JE, Berkman LF.Clark CR, et al.BMC Public Health. 2012 Mar 20;12:211. doi: 10.1186/1471-2458-12-211.BMC Public Health. 2012.PMID: 22433166Free PMC article.
Clark CR, Ommerborn MJ, A Coull B, Pham do Q, Haas JS.Clark CR, et al.Med Care. 2016 Jun;54(6):555-61. doi: 10.1097/MLR.0000000000000525.Med Care. 2016.PMID: 26974677Free PMC article.