1. Division of Orthopaedic Surgery, McMaster University, Hamilton, Ontario, Canada
2. Centre for Evidence Based Orthopaedics, McMaster University, Hamilton, Ontario, Canada
3. Centre for Evidence Based Orthopaedics, Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada
4. Division of Orthopaedic Surgery, Harvard Medical School, Boston, Massachusetts, USA
5. Division of Orthopaedic Surgery, Department of Surgery, McMaster University, Hamilton, Ontario, Canada