[1] Univ Massachusetts, Sch Med, Worcester, MA USA
[2] Carolinas Med Ctr, Charlotte, NC 28203 USA
[3] Univ Arizona, Tucson, AZ USA
[4] Massachusetts Gen Hosp, Boston, MA 02114 USA
[5] Christiana Care Hlth Syst, Newark, DE USA
[6] Washington Univ, Sch Med, St Louis, MO USA
[7] Univ Ottawa, Ottawa, ON, Canada
[8] Dalhousie Univ, St John, NB, Canada
[9] Intermt Med Ctr, Salt Lake City, UT USA
[10] Univ Utah, Salt Lake City, UT USA
[11] LSU Hlth Sci Ctr, Baton Rouge, LA USA
[12] North Shore Univ Hosp, Manhasset, NY USA
[13] Advocate Christ Med Ctr, Chicago, IL USA
[14] Brown Univ, Providence, RI 02912 USA
[15] Duke Univ, Sch Med, Durham, NC USA
[16] Brigham & Womens Hosp, 75 Francis St, Boston, MA 02115 USA
[17] Indiana Univ, Indianapolis, IN 46204 USA
[18] Yale Univ, Sch Med, New Haven, CT USA
[19] NYU, Bellevue Hosp, New York, NY USA
[20] Kingston Gen Hosp, Kingston, ON, Canada
[21] Castle Hosp, Kailua, HI USA