1. Department of Ultrasound, Peking University Third Hospital, 49 N Garden Rd, Beijing 100191, China.
2. Department of Ultrasound, The First Affiliated Hospital of Medical College of Shihezi University, Xinjiang, China.
3. Department of Breast Sonography, Center for Diagnosis and Treatment of Breast Diseases, Yili Maternity and Child Health Hospital, Xinjiang, China.
4. Department of Ultrasound, Jinzhong First People's Hospital, Jinzhong City, China.
5. Ultrasound Department of The Second Affiliated Hospital, School of Medicine, The Chinese University of Hong Kong, Shenzhen & Longgang District People's Hospital of Shenzhen, Shenzhen, China.
6. Department of Ultrasound, Liaocheng Dongchangfu District Maternal and Child Care Service Center, Shandong, China.
7. Department of Ultrasound, Beijing HaiDian Hospital, Beijing, China.
8. Department of Ultrasound, The Second People's Hospital of Zhangqiu District, Jinan, China.
9. Department of Ultrasound, Port Hospital of Hebei Port Group Co. LTD, Qinhuangdao City, China.