[1] Thomas Jefferson Univ, Sidney Kimmel Med Coll, Dept Anesthesiol, Philadelphia, PA 19107 USA
[2] Rush Med Coll, Dept Anesthesiol, Chicago, IL 60612 USA
[3] Wake Forest Sch Med, Dept Anesthesiol, Winston Salem, NC USA
[4] Wake Forest Sch Med, Dept Publ Hlth Sci, Winston Salem, NC USA
[5] Univ Pittsburgh, Dept Anesthesiol, Pittsburgh, PA USA
[6] Univ Pittsburgh, Dept Psychiat, Pittsburgh, PA USA
[7] Western Reserve Hosp, Dept Anesthesiol, Akron, OH USA
[8] Western Reserve Hosp, Dept Neurosurg, Akron, OH USA
[9] Univ Toronto, Dept Anesthesiol, Toronto, ON, Canada
[10] Michigan State Univ, Coll Human Med, Procare Pain Solut, Grand Rapids, MI USA
[11] Michigan State Univ, Coll Human Med, Dept Anesthesiol, Grand Rapids, MI USA
[12] Mayo Coll Med, Dept Anesthesiol, Rochester, MN USA
[13] Mayo Coll Med, Dept Psychiat, Rochester, MN USA
[14] Johns Hopkins Sch Med, Dept Anesthesiol & Crit Care Med, Bethesda, MD USA
[15] Johns Hopkins Sch Med, Dept Neurol, Bethesda, MD USA
[16] Johns Hopkins Sch Med, Dept Phys Med & Rehabil, Bethesda, MD USA
[17] Uniformed Serv Univ Hlth Sci, Bethesda, MD 20814 USA