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.
Forsblom CM, Groop PH, Ekstrand A, Groop LC.Forsblom CM, et al. Among authors: groop lc, groop ph.BMJ. 1992 Oct 31;305(6861):1051-3. doi: 10.1136/bmj.305.6861.1051.BMJ. 1992.PMID: 1467683Free PMC article.