1. Outpatient DepartmentWest China Hospital of Sichuan University Chengdu China
2. Division of NephrologyWest China Hospital of Sichuan University Chengdu China
3. Kidney Research InstituteWest China Hospital of Sichuan University Chengdu China
4. Department of Internal MedicineLouis A Weiss Memorial Hospital Chicago Illinois USA
5. Department of BiostatisticsSchool of Public Health, University of Michigan Ann Arbor Michigan USA
6. Kidney Epidemiology and Cost CenterUniversity of Michigan Ann Arbor Michigan USA