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.
Alexander JP, Barron DW.Alexander JP, et al. Among authors: barron dw.Br Med J (Clin Res Ed). 1983 Apr 2;286(6371):1148. doi: 10.1136/bmj.286.6371.1148.Br Med J (Clin Res Ed). 1983.PMID: 6404370Free PMC article.No abstract available.