1. Department of Family and Community Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
2. Center for Worker Health, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
3. Section on Gerontology and Geriatric Medicine, Department of Internal Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
4. Department of Physical Therapy, School of Health Sciences, Winston-Salem State University, Winston-Salem, North Carolina, USA
5. Department of Epidemiology and Prevention, Division of Public Health Sciences, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
6. Department of Neurology, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA