[1
]
Institute of Neurology, Huashan Hospital, Fudan University, Shanghai, China.
[2
]
Department of Health Statistics, School of Public Health, Fudan University, Shanghai,
China.
[3
]
Department of Epidemiology and Biostatistics, College of Public Health, University
of South Florida, Tampa, FL, USA.
[4
]
Institute of Neurology, Huashan Hospital, Fudan University, Shanghai, China. Electronic
address: profzhong@sina.com.cn.