[1] Loyola Univ Chicago, Stritch Sch Med, Chicago, IL 60660 USA
[2] Univ Miami, Miller Sch Med, Coral Gables, FL 33124 USA
[3] Barrow Neurosurg Associates, Phoenix, AZ USA
[4] Mayo Clin, Rochester, MN USA
[5] Univ Nebraska Med Ctr, Omaha, NE USA
[6] Evidence Based Hlth Serv Inc, Suita, Osaka, Japan
[7] HCA Midwest, Kansas City, KS USA
[8] Washington Univ, St Louis, MO 63130 USA
[9] Cedars Sinai Med Ctr, Los Angeles, CA USA
[10] Stanford Univ, Stanford, CA 94305 USA
[11] Univ Alberta, Edmonton, AB T6G 2M7, Canada
[12] Tufts Med Ctr, Boston, MA USA
[13] Univ Washington, Seattle, WA 98195 USA