The 2 registries RDPLF and Rein are information systems concerning the treatment of end-stage renal disease. The aim of the study was to evaluate the representativeness and exhaustivity of the recorded cases as well as the accuracy of the informations in the 2 registries. Were included 375 adults, who started a first ESRD treatment between 1 January 2003 and 31 December 2003 in 7 French regions and were treated by peritoneal dialysis (PD) on the first day of the 4th month of ESRD treatment. 264 patients were identified found in both registries. Age, body mass index and albuminemia didn't differ significantly. The mean haemoglobin level was higher in RDPLF. There was a good concordance on sex, diabetes status but less so on primary renal disease and PD modalities. There were significant discrepancies between the two registries on the date of the first treatment. The analysis of outcomes (transplantation or death) showed 8 discrepancies related to the lack of recording of the event in one of the 2 registries. The good global agreement observed between Rein and RDPLF for the common data emphasizes the fiability and representativeness of the 2 structures and the synergy of their activities for a best evaluation of the quality of peritoneal dialysis. This study shows the necessity of a common patient identification that will allow us to maintain a good complementarity between the 2 registries and will favour common studies.