[1] Columbia Univ, Vagelos Coll Phys & Surg, Columbia Bassett Program, New York, NY 10027 USA
[2] Bassett Med Ctr, Columbia Bassett Program, Cooperstown, NY 13326 USA
[3] Bassett Med Ctr, Bassett Res Inst, Cooperstown, NY 13326 USA
[4] Columbia Univ, Dept Pediat, Vagelos Coll Phys & Surg, New York, NY 10027 USA
[5] Univ Minnesota, Sch Publ Hlth, Div Epidemiol & Community Hlth, Minneapolis, MN USA