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.
Crumley ET, Wiebe N, Cramer K, Klassen TP, Hartling L.Crumley ET, et al. Among authors: hartling l.BMC Med Res Methodol. 2005 Aug 10;5:24. doi: 10.1186/1471-2288-5-24.BMC Med Res Methodol. 2005.PMID: 16092960Free PMC article.Review.
Klassen TP, Hartling L, Hamm M, van der Lee JH, Ursum J, Offringa M.Klassen TP, et al. Among authors: hartling l.Lancet. 2009 Oct 17;374(9698):1310-2. doi: 10.1016/S0140-6736(09)61803-1.Lancet. 2009.PMID: 19837237No abstract available.