1. Clinical Research Center, School of Medicine, Shanghai Ninth People’s Hospital Affiliated to Shanghai JiaoTong University, Shanghai, China
2. Department of Medical Service, Naval Hospital of Eastern theater, Zhejiang, Zhoushan, China
3. Department of Health Statistics, Second Military Medical University, Shanghai, China
4. Clinical Epidemiology and Biostatistics, School of Medical Sciences, Örebro University, Örebro, Sweden