1. Department of Psychiatry and Behavioral Sciences; Duke University Medical Center; Durham North Carolina
2. Department of Medicine; Duke University Medical Center; Durham North Carolina
3. Center for Aging and Human Development; Duke University Medical Center; Durham North Carolina
4. Department of Medicine, King Abdulaziz University; Jeddah Saudi Arabia
5. School of Public Health, Ningxia Medical University; Yinchuan People's Republic of China
6. Department of Research; Glendale Adventist Medical Center; Glendale California
7. Duke University; Durham North Carolina