Mainous Arch G, Baker Richard, Majeed Azeem, Koopman Richelle J, Everett Charles J, Saxena Sonia, Tilley Barbara C
Department of Family Medicine, Medical University of South Carolina, Charleston 29425, USA.
Public Health Rep. 2006 May-Jun;121(3):331-6. doi: 10.1177/003335490612100317.