[1] Univ Texas, Hlth Sci Ctr, Dept Med, San Antonio, TX 78284 USA
[2] Univ Vermont, Coll Med, Dept Pathol, Lab Clin Biochem Res, Burlington, VT 05405 USA
[3] Wake Forest Univ, Bowman Gray Sch Med, Dept Publ Hlth Sci, Winston Salem, NC 27103 USA
[4] Eli Lilly & Co, Area Med Ctr, Vienna, Austria