[1] Sunnybrook Hlth Sci Ctr, Dept Cardiol, Toronto, ON M4N 3M5, Canada
[2] Sunnybrook Hlth Sci Ctr, Dept Res Design & Biostat, Toronto, ON M4N 3M5, Canada
[3] Sunnybrook Hlth Sci Ctr, Div Nephrol, Toronto, ON M4N 3M5, Canada
[4] Mem Univ Newfoundland, Dept Family Med, St John, NF, Canada
[5] McGill Univ, Dept Family Med, Montreal, PQ H3A 2T5, Canada
[6] Univ British Columbia, Dept Family Practice, Vancouver, BC V5Z 1M9, Canada