The critera for study selection is spelled out quite well in the methods section of the article.
I know many of the physicians who conducted this systematic review. Obviously they do have some of their own biases but the results of the paper speak for themselves. It is always difficult to perform this type of research and it would seem there were a paucity of studies from which to draw conclusions.
There are also numerous issues with prescription drug costs and support from the US vs Canada, the access to expensive care and surgical interventions in the US compared to Canada, who pays for R & D for medications, new developments in technology, etc.
What I do find impressive is that for the conditions noted in the article, the single payer format in Canada seems to do about as well as the US (or better ?? with End Stage Renal Disease).
I have not read the study in detail yet, but for all the money we pay in the US for healthcare, I would hope that we would have a little better comparison than this.
From what little I understand about how the Canadian health systems operates (and it is very little at that), I thought that Canada achieved successful outcomes by concentrating their treatment on the cases where a positive outcome is possible or likely, and writing off the no-hopers and CTDs. Basically, triage techniques writ large. While that is possible in a system where the patients are homogeneous from a policy perspective, I don’t think it’ll teach many useful lessons to the American health care system where different insurance plans effectively prioritize patients for different treatments.