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.
Mehrotra A, Ashwood JS.Mehrotra A, et al. Among authors: ashwood js.Health Aff (Millwood). 2016 May 1;35(5):938. doi: 10.1377/hlthaff.2016.0373.Health Aff (Millwood). 2016.PMID: 27141005No abstract available.
STARSurg Collaborative; Nepogodiev D.STARSurg Collaborative, et al.BMC Med Res Methodol. 2019 Dec 12;19(1):237. doi: 10.1186/s12874-019-0857-y.BMC Med Res Methodol. 2019.PMID: 31830925Free PMC article.