Affiliation: | Ping Xu, Min Yang, Lan-Ying Wu, Department of Ultrasound, Beijing Shijitan Hospital Affiliated to Capital Medical University, Beijing 100038, ChinaMei Wu, Zheng-Min Ruan, Department of Ultrasound, The Second Hospital of Shandong University, Jinan 250033, Shandong Province, ChinaJuan Xiao, Evidence-based Medicine Center, The Second Hospital of Shandong University, Jinan 250033, Shandong Province, China |