[1] Univ Massachusetts, Sch Med, 55 Lake Ave North, Worcester, MA 01655 USA
[2] Indiana Univ, Med Ctr, Indianapolis, IN USA
[3] Univ Alabama Birmingham, Sch Med, Birmingham, AL USA
[4] UPMC Presbyterian, Pittsburgh, PA USA
[5] Digest Hlth Specialists, Tupelo, MS USA
[6] Wake Forest Univ, Bowman Gray Sch Med, Winston Salem, NC USA
[7] St Louis Univ, Sch Med, St Louis, MO USA
[8] Palmetto Hlth Richland, Columbia, SC USA
[9] Cleveland Clin Fdn, 9500 Euclid Ave, Cleveland, OH 44195 USA
[10] Dartmouth Hitchcock Med Ctr, Lebanon, NH 03766 USA
[11] Johns Hopkins Med Hosp, Baltimore, MD USA
[12] Stanford Univ, Sch Med, Stanford, CA 94305 USA