1. Geriatric Research, Education and Clinical Center, Veteran's Affairs Medical Center, Durham, North Carolina.
2. Curriculum in Human Movement Science, School of Public Health, University of North Carolina–Chapel Hill, Chapel Hill, North Carolina.
3. Center for the Study of Aging and Human Development and Older Americans Independence Center, Duke University, Durham, North Carolina.
4. Department of Epidemiology, School of Public Health, University of North Carolina–Chapel Hill, Chapel Hill, North Carolina.
5. Institute for Research in Extramural Medicine, VU University Medical Center, Amsterdam, The Netherlands.
6. Department of Physical Therapy, University of Pittsburgh, Pittsburgh, Pennsylvania.
7. Sticht Center on Aging, Wake Forest University School of Medicine, Winston-Salem, North Carolina.
8. Department of Medicine, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania.
9. Department of Epidemiology and Biostatistics, University of California, San Francisco, California.
10. Department of Preventive Medicine, University of Tennessee, Memphis, Tennessee.
11. Clinical Research Branch, National Institute on Aging, Baltimore, Maryland.
12. Division of Geriatric Medicine and Gerontology, Johns Hopkins University School of Medicine, Baltimore, Maryland.