[1] Univ Virginia Hlth Syst, Dept Pediat, Div Cardiol, Charlottesville, VA 22908 USA
[2] Univ Virginia Hlth Syst, Dept Publ Hlth Sci, Div Clin Informat, Charlottesville, VA 22908 USA
[3] Univ Virginia Hlth Syst, Dept Publ Hlth Sci, Div Biostat & Epidemiol, Charlottesville, VA 22908 USA