Affiliation: | 1. New England Geriatrics Research, Education, and Clinical Center, VA Boston Health Care System, Boston, Massachusetts, USA;2. Massachusetts Veterans Epidemiology Research and Information Center, VA Boston Health Care System, Boston, Massachusetts, USA;3. New England Geriatrics Research, Education, and Clinical Center, VA Boston Health Care System, Boston, Massachusetts, USA Massachusetts Veterans Epidemiology Research and Information Center, VA Boston Health Care System, Boston, Massachusetts, USA Department of Physical Medicine and Rehabilitation, Harvard Medical School, Boston, Massachusetts, USA;4. Massachusetts Veterans Epidemiology Research and Information Center, VA Boston Health Care System, Boston, Massachusetts, USA Division of Aging, Brigham & Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA;5. New England Geriatrics Research, Education, and Clinical Center, VA Boston Health Care System, Boston, Massachusetts, USA Division of Aging, Brigham & Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA;6. Massachusetts Veterans Epidemiology Research and Information Center, VA Boston Health Care System, Boston, Massachusetts, USA Department of Biostatistics, Boston University School of Public Health, Boston, Massachusetts, USA |