1. Department of Geriatrics and National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China
2. School of Nursing, The University of Texas at Austin, Austin
3. School of Nursing, The Johns Hopkins University, Baltimore, Maryland
4. Hinda and Arthur Marcus Institute for Aging Research, Hebrew SeniorLife, Boston, Massachusetts
5. Department of Breast Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China
6. Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts