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.
China L, Muirhead N, Skene SS, Shabir Z, De Maeyer RP, Maini A, Gilroy DW, O'Brien AJ.China L, et al. Among authors: gilroy dw.BMJ Open. 2016 Jan 25;6(1):e010132. doi: 10.1136/bmjopen-2015-010132.BMJ Open. 2016.PMID: 26810999Free PMC article.Clinical Trial.