Initiating chronic dialysis has major implications for patients and health care systems. Within the spectrum of severity of

chronic kidney disease, there is a need to identify a threshold before which starting dialysis offers no benefit to the patient but beyond which there may be some measurable risk.

Identifying this threshold remains a challenge because of the inaccuracy of creatinine-based measures of kidney function; a body of evidence composed of potentially biased observational data; and reliance on poorly validated nutritional surrogate markers, with an underemphasis on patient-important outcomes such as hospital admission and quality of life. Collectively,

these factors may account in part for the recent increase in earlier (i.e., at a higher level of kidney function) initiation of dialysis in Canada and the United States. Considering the enormous burden imposed by dialysis on patients and health care systems, there is a need for a judicious approach to dialysis initiation.

The Initiating Dialysis Early and Late (IDEAL) study, builds on the prior observational experience with timing of dialysis initiation and has prompted us to revisit the previous guidelines by the Canadian Society of Nephrology