[1] George Washington Univ, Sch Med & Hlth Sci, Dept Surg, Washington, DC 20052 USA
[2] Howard Univ, Coll Med, Dept Surg, Washington, DC USA
[3] Childrens Natl Med Ctr, Dept Pediat Surg, Washington, DC 20010 USA
[4] Univ Baltimore, Merrick Sch Business, Dept Hlth Management, Baltimore, MD 21201 USA
[5] Childrens Natl Med Ctr, Dept Lab Med, Washington, DC 20010 USA