1. Population Science, Pennington Biomedical Research Center, Baton Rouge, Louisiana.
2. Exercise and Health Sciences, College of Nursing and Health Sciences, University of Massachusetts, Boston, Massachusetts.
3. Preventive Medicine, Pennington Biomedical Research Center, Baton Rouge, Louisiana.
4. Department of Preventive Medicine Northwestern University Feinberg School of Medicine, Chicago, Illinois.
5. Division of Research, Kaiser Permanente, Oakland, California.
6. Division of Preventive Medicine, School of Medicine, University of Alabama, Birmingham, Alabama.