Mi Ah Han1, Yuting Wang2, Gordon Guyatt3. 1. Department of Preventive Medicine, College of Medicine, Chosun University, Gwangju, Republic of Korea 2. Department of Health Research Methods, Evidence and Impact, McMaster University, Hamilton, Ontario, Canada 3. Department of Health Research Methods, Evidence and Impact, McMaster University, Hamilton, Ontario, Canada. guyatt@mcmaster.ca