[1] Yale Univ, Sch Med, New Haven, CT USA
[2] Columbia Univ, Columbia Bassett Program, Vagelos Coll Phys & Surg, New York, NY USA
[3] Bassett Med Ctr, Columbia Bassett Program, Cooperstown, NY USA
[4] Bassett Med Ctr, Bassett Res Inst, Cooperstown, NY USA
[5] SUNY Upstate Med Univ, Coll Med, Syracuse, NY 13210 USA
[6] Columbia Univ, Dept Pediat, Vagelos Coll Phys & Surg, New York, NY 10027 USA