Evidence-Based Medicine Center, School of Basic Medical Sciences, Lanzhou University, Lanzhou, China. Lanzhou University Institute of Health Data Science, Lanzhou, China. School of Public Health, Lanzhou University, Lanzhou, China. Department of Respiratory Medicine, Children's Hospital of Chongqing Medical University, Chongqing, China. National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China. Chongqing Key Laboratory of Pediatrics, Chongqing, China. The First School of Clinical Medicine, Lanzhou University, Lanzhou, China. Paediatric Intensive Care Unit, Hospital General Universitario Gregorio Marañón, Calle Doctor Castelo 47, 28007, Madrid, Spain. Department of Respiratory Medicine, Children's Hospital of Chongqing Medical University, Chongqing, China. emliu186@126.com. National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China. emliu186@126.com. Chongqing Key Laboratory of Pediatrics, Chongqing, China. emliu186@126.com. Evidence-Based Medicine Center, School of Basic Medical Sciences, Lanzhou University, Lanzhou, China. chenyaolong@lzu.edu.cn. Lanzhou University Institute of Health Data Science, Lanzhou, China. chenyaolong@lzu.edu.cn. School of Public Health, Lanzhou University, Lanzhou, China. chenyaolong@lzu.edu.cn. WHO Collaborating Centre for Guideline Implementation and Knowledge Translation, Lanzhou, China. chenyaolong@lzu.edu.cn. Lanzhou University GRADE Center, Lanzhou, China. chenyaolong@lzu.edu.cn.