1. Department of Pediatrics (J.D.M., M.L.L., P.C., K.M.), Faculty of Medicine, University of Ottawa, Children's Hospital of Eastern Ontario, Ottawa, Canada K1H 8L1;
2. Research Institute (J.D.M., M.L.L., P.C., K.M.), Children's Hospital of Eastern Ontario, Ottawa, Canada K1H 8L1;
3. Department of Anesthesia (D.R.D.), Faculty of Medicine, University of Ottawa and Children's Hospital of Eastern Ontario, Ottawa, Canada K1H 8L1;
4. Department of Intensive Care (D.R.D.), Temple Street Children's University Hospital Dublin and University College Dublin 1, Ireland;
5. Ontario Newborn Screening Laboratory (O.Y.A.-D., P.C.), Children's Hospital of Eastern Ontario, Ottawa, Canada K1H 8L1;
6. Clinical Epidemiology Program (T.R.), Ottawa Hospital Research Institute, Ottawa, Ontario, Canada K1H 8L6;
7. Department of Epidemiology and Community Medicine (T.R.), Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada K1H 8L6