AbstractsThe annual survey of Japanese Society for Dialysis Therapy Renal Data Registry (JRDR) was conducted for 4380 dialysis facilities at the end of 2015, among which 4321 facilities (98.7%) responded. The response rate of the 2015 survey was comparable with the past, even though it was the first year after the new anonymization method. The number of chronic dialysis patients in Japan continues to increase every year; it has reached 324,986 at the end of 2015. The mean age was 67.86 years. At the end of 2015, the prevalence rate was 2592 patients per million population. Diabetic nephropathy was the most common primary disease among the prevalent dialysis patients (38.4%), followed by chronic glomerulonephritis (29.8%) and nephrosclerosis (9.5%). The rate of diabetic nephropathy and nephrosclerosis has been increasing year by year, whereas that of chronic glomerulonephritis was declining. The number of incident dialysis patients during 2015 was 39,462; it has remained stable since 2008. The average age was 69.20 years, and diabetic nephropathy (43.7%) was the most common cause in the incident dialysis patients. These patients caused by diabetes did not change in number for the last several years. Meanwhile, 31,608 patients died in 2015; the crude mortality rate was 9.6%. The patients treated by hemodiafiltration (HDF) have been increasing rapidly from the revision of medical reimbursement for HDF therapy in 2012. It has attained 53,776 patients at the end of 2015, which were 10,493 greater than that in 2014. In particular, the number of online HDF patients increased about ten times 2012. The number of peritoneal dialysis (PD) patients was 9322 in 2015, which was slightly increased than 2014. Twenty percent of PD patients treated in the combination of hemodialysis (HD) or HDF therapy. Five hundred seventy-two patients underwent home HD therapy at the end of 2015; it increased by 43 from 2014. Further JRDR data analyses could clarify the relationships between various dialysis modalities, patient care, and clinical outcomes; furthermore, it could also make it possible to establish clinical practice guidelines or medical reimbursement revisions based on the evidence. Japanese Society for Dialysis Therapy (JSDT) has conducted a survey (JSDT Renal Data Registry: JRDR) on the status of chronic dialysis therapy in Japan at the end of every year since 1968, covering almost all dialysis facilities throughout the country [1,2]. Despite the fact that this survey is conducted without providing any compensation to participating facilities, its response rate represents a largely complete and unbiased survey of the status of chronic dialysis in Japan, making it quite rare in the world. In publishing our results, we would like to take this opportunity to express our sincere gratitude to everyone at the participating dialysis facilities for taking part in the survey in addition to their routine clinical practice.JRDR had previously featured two types of reports: prompt (unfixed) data reported at the annual meeting held every J...