Systems for grading the quality of evidence and the strength of recommendations I: Critical appraisal of existing approaches The GRADE Working Group
David Atkins, Martin Eccles, Signe Flottorp, Gordon H Guyatt, David Henry, Suzanne Hill, Alessandro Liberati, Dianne O'Connell, Andrew D Oxman, Bob Phillips, Holger Schünemann, Tessa TT Edejer, Gunn E Vist*, John W Williams and The GRADE Working Group