The US Renal Data System (USRDS) is the largest and most comprehensive national end-stage renal disease (ESRD) and chronic kidney disease (CKD) surveillance system in the world. Supported by the Centers for Medicare & Medicaid Services and the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) at the National Institutes of Health, the USRDS Coordinating Center is operated by the University of Michigan at the Kidney Epidemiology and Cost Center (KECC), in partnership with Arbor Research Collaborative for Health, in Ann Arbor, Michigan.