1. Durham Veterans Affairs Geriatric Research Education and Clinical Center, Durham Veterans Affairs Health Care System (VAHCS), North Carolina, USA
2. Center of Innovation to Accelerate Discovery and Practice Transformation, Durham Veterans Affairs Health Care System, North Carolina, USA
3. Center for the Study of Aging and Human Development (the Aging Center), Duke University, Durham, North Carolina, USA
4. Department of Biostatistics and Bioinformatics, Duke University, Durham, North Carolina, USA
5. Department of Population Health Sciences, Duke University, Durham, North Carolina, USA