作者单位:NephroCare Country Italy, Italy[1]Unit of Biometry and Clinical Epidemiology, Fondazione IRCCS Policlinico 'San Matteo', Pavia, Italy[2]NephroCare EMEALA Medical Board, Bad Homburg, Germany[3]Department of Nephrology, Dialysis and Transplantation, Fondazione IRCCS Policlinico 'San Matteo[4]