[1] Univ Pittsburgh, Childrens Hosp Pittsburgh UPMC, Sch Med, Div Gen Acad, Pittsburgh, PA USA
[2] Univ Pittsburgh, Childrens Hosp Pittsburgh UPMC, Sch Med, Dept Urol, Pittsburgh, PA USA
[3] Childrens Hosp Philadelphia, Ctr Pediat Clin Effect, Div Gen Pediat, Philadelphia, PA 19104 USA
[4] Univ N Carolina, Dept Biostat, Collaborat Studies Coordinating Ctr, Chapel Hill, NC USA
[5] So Illinois Univ, Sch Med, Div Urol, Springfield, IL USA
[6] Wayne State Univ, Childrens Hosp Michigan, Detroit, MI USA
[7] NIDDK, Bethesda, MD 20892 USA
[8] George Washington Univ, Sch Med, Childrens Natl Med Ctr, Div Urol, Washington, DC USA
[9] SUNY Buffalo, Sch Med & Biomed Sci, Div Pediat Urol, Buffalo, NY 14260 USA