[1] Father Sean OSullivan Res Ctr, Ctr Evaluat Med, St Josephs Healthcare, Hamilton, ON L8N 2G6, Canada
[2] McMaster Univ, Dept Surg, Hamilton, ON L8S 4L8, Canada
[3] McMaster Univ, Dept Clin Epidemiol & Biostat, Hamilton, ON L8S 4L8, Canada
[4] McMaster Univ, Dept Comp & Software, Hamilton, ON L8S 4L8, Canada