[1] Childrens Hosp Philadelphia, Div Cardiol, Philadelphia, PA USA
[2] Univ Florida, Coll Publ Hlth & Hlth Profess, Dept Epidemiol, Gainesville, FL USA
[3] Univ Penn, Dept Biostat & Epidemiol, Perelman Sch Med, Philadelphia, PA USA
[4] Boston Childrens Hosp, Div Cardiol, Boston, MA USA
[5] Texas Childrens Hosp, Div Cardiol, Houston, TX USA
[6] Cincinnati Childrens Med Ctr, Div Cardiol, Cincinnati, OH USA
[7] Childrens Hosp Philadelphia, Dept Cardiothorac Surg, Philadelphia, PA USA
[8] Univ Alberta, Div Cardiothorac Surg, Edmonton, AB, Canada
[9] Univ Alberta, Div Cardiol, Edmonton, AB, Canada
[10] Childrens Hosp Philadelphia, 34th St & Civ Ctr Blvd, Philadelphia, PA 19104 USA