1. Department of Respiratory Medicine, Lanzhou University First Clinical Medical College, Lanzhou, China
2. Department of Orthopedics, Lanzhou University First Clinical Medical College, Lanzhou, China
3. Evidence-Based Medicine Center, School of Basic Medical Sciences, Lanzhou University, Lanzhou, Gansu, China
4. Department of Respiratory and Critical Care Medicine, The First Hospital of Lanzhou University, Lanzhou, Gansu, China