Paul S Echlin1
, Ross EG Upshur2,3,4
, Douglas B McKeag5
and Harsha P Jayatilake6 
1Providence Athletic Medicine, Providence Hospital and Medical Centers, 47601 Grand River Avenue, Suite 101, Novi Michigan, United States of America 48374
2Primary Care Research Unit, Department of Family and Community Medicine, Sunnybrook and Women's College Health Sciences Centre, 2075 Bayview Avenue, #E-349, Toronto, Ontario, Canada M4N 3M5
3Department of Family and Community Medicine, University of Toronto, 263 McCaul Street, Toronto, Ontario, Canada M5T 1W7
4Department of Public Health Sciences, University of Toronto, 12 Queen's Park Crescent W., Toronto, Ontario, Canada M5S 1A8
5Department of Family Medicine, Indiana University, Long Hospital, Second Floor. 1110 West Michigan Street, Indianapolis Indiana, United States of America 46202-5102
6Department of Family Medicine, Wayne State University, 15400 West McNichols, 2nd Floor, Detroit, Michigan, United States of America 48235