1. Lanzhou University; First Clinical Medical College; No. 199, Donggang West Road, Chengguan District Lanzhou Gansu China 730000
2. The Second Xiangya Hospital of Central South University; Department of Breast-Thyroid Surgery; Changsha China
3. Lanzhou University; Evidence-Based Medicine Center, School of Basic Medical Sciences; No. 199, Donggang West Road Lanzhou City Gansu China 730000
4. Lanzhou University; Key Laboratory of Evidence Based Medicine and Knowledge Translation of Gansu Province; No. 199, Donggang West Road Lanzhou City Gansu China 730000