1. Department of Family Medicine, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.
2. The Cecil G. Sheps Center for Health Services Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.
3. Division of Geriatric Medicine and Palliative Care Program, School of Medicine, University of North Carolina, Chapel Hill, North Carolina, USA.
4. School of Nursing, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.
5. School of Social Work, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.