1. Department of Nephropathy; Xiangya Hospital; Central South University; Changsha Hunan China
2. Department of Medical Records Information; Xiangya Hospital; Central South University; Changsha Hunan China
3. Department of Epidemiology and Community Medicine; University of Ottawa; Ottawa ON Canada
4. OMNI Research Group; Department of Obstetrics and Gynecology; University of Ottawa; Ottawa ON Canada
5. Ottawa Hospital Research Institute Clinical Epidemiology Program; Ottawa ON Canada
6. Department of Obstetrics and Gynaecology; Southern Medical University; Guangzhou Guangdong China
7. Department of Urology; The Third Xiangya Hospital of Central South University; Changsha Hunan China