[1
]
National Center for Chronic and Non-communicable Disease Control and Prevention, Chinese
Center for Disease Control and Prevention, Beijing 100050, China.
[2
]
Clinical Trial Service Unit and Epidemiological Studies Unit (CTSU), University of
Oxford, UK.
[3
]
Clinical Trial Service Unit and Epidemiological Studies Unit (CTSU), University of
Oxford, UK. Electronic address: zhengming.chen@ctsu.ox.ac.uk.
[4
]
National Center for Chronic and Non-communicable Disease Control and Prevention, Chinese
Center for Disease Control and Prevention, Beijing 100050, China. Electronic address:
linhong@chinawch.org.cn.