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.
Campbell SM, Fuat A, Summerton N, Lancaster N, Hobbs FR.Campbell SM, et al.Br J Gen Pract. 2011 Jul;61(588):e427-35. doi: 10.3399/bjgp11X583218.Br J Gen Pract. 2011.PMID: 21722451Free PMC article.
Campbell SM, Roland MO, Bentley E, Dowell J, Hassall K, Pooley JE, Price H.Campbell SM, et al.Br J Gen Pract. 1999 Dec;49(449):967-70.Br J Gen Pract. 1999.PMID: 10824340Free PMC article.
Marshall M, Sheaff R, Rogers A, Campbell S, Halliwell S, Pickard S, Sibbald B, Roland M.Marshall M, et al.Br J Gen Pract. 2002 Aug;52(481):641-5.Br J Gen Pract. 2002.PMID: 12171222Free PMC article.
Campbell S, Steiner A, Robison J, Webb D, Raven A, Roland M.Campbell S, et al.Br J Gen Pract. 2003 Apr;53(489):298-304.Br J Gen Pract. 2003.PMID: 12879830Free PMC article.