1. Division of Preventive Medicine, University of Alabama at Birmingham, Birmingham, AL
2. Department of Surgery, University of Alabama at Birmingham, Birmingham, AL
3. Department of Epidemiology, University of Alabama at Birmingham, Birmingham, AL
4. Division of Cardiovascular Medicine, Howard University College of Medicine, Washington, DC
5. Department of Medicine, University of Mississippi Medical Center, Jackson, MS
6. Birmingham Veterans Affairs Medical Center, Birmingham, AL