Birken Catherine S, Parkin Patricia C, To Teresa, Macarthur Colin
Division of Paediatric Medicine and the Paediatric Outcomes Research Team, The Hospital for Sick Children, and the Department of Paediatrics, University of Toronto, Toronto, Ont.
CMAJ. 2006 Oct 10;175(8):867. doi: 10.1503/cmaj.051207. Epub 2006 Sep 22.