1. Department of Nephrology, Peking Union Medical College Hospital; Chinese Academy of Medical Sciences & Peking Union Medical College; Beijing China
2. School of Nursing; Chinese Academy of Medical Sciences & Peking Union Medical College; Beijing China
3. Department of Epidemiology & Biostatistics; Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College; Beijing China
4. School of Nursing; Johns Hopkins University; Baltimore USA
5. Division of Nephrology; Massachusetts General Hospital; Boston MA USA