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.
Berglund A, von Euler M, Schenck-Gustafsson K, Castrén M, Bohm K.Berglund A, et al. Among authors: bohm k.BMJ Open. 2015 Apr 28;5(4):e007661. doi: 10.1136/bmjopen-2015-007661.BMJ Open. 2015.PMID: 25922106Free PMC article.