1. From the Montreal Chest Institute, McGill University, Montreal, Quebec, Canada; University of Alberta, Edmonton, Alberta, Canada; University of Toronto and St. Michael's Hospital, Toronto, Ontario, Canada; University of Saskatchewan, Saskatoon, Saskatchewan, Canada; Gama Filho University, Rio de Janeiro, Brazil; and King Abdulaziz Medical City, King Abdulaziz Bin Saud University, Riyadh, Saudi Arabia.