[1] Johns Hopkins Bloomberg Sch Publ Hlth, METRC Coordinating Ctr, Baltimore, MD USA
[2] Carolinas Med Ctr, Charlotte, NC 28203 USA
[3] Univ Maryland, R Adams Cowley Shock Trauma Ctr, Baltimore, MD 21201 USA
[4] MetroHlth Med Ctr, Cleveland, OH USA
[5] Vanderbilt Univ, Med Ctr, Nashville, TN USA
[6] Inova Fairfax Hosp, Falls Church, VA USA
[7] Johns Hopkins Univ, Sch Med, Baltimore, MD USA
[8] Denver Hlth & Hosp Author, Denver, CO USA
[9] Tampa Gen Hosp, Florida Orthoped Inst, Tampa, FL 33606 USA
[10] Reg Hosp, Hennepin Cty Med Ctr, Minneapolis, MN USA
[11] Univ Texas Hlth Sci Ctr Houston, Houston, TX 77030 USA
[12] Methodist Hosp, Indianapolis, IN USA
[13] Orthopaed Associates Michigan, Grand Rapids, MI USA
[14] Wake Forest Univ, Baptist Med Ctr, Winston Salem, NC 27109 USA