Ran, Min
Peng, Linli
Liu, Qin
Pender, Michelle
He, Fang
Wang, Hong
Funding for this research was provided by:
Research Special Fund for Public Welfare Industry of Health (No.201202010)
Article History
Received: 17 January 2018
Accepted: 1 October 2018
First Online: 19 October 2018
Ethics approval and consent to participate
: The study has been approved by Biomedical Ethics Committee of Peking University and the Chongqing medical university Committee. Written consent was obtained from every participant and parents or guardians of minors involved in this study. The consent forms were approved by Commission of Sha Ping-Ba district.
: Not applicable.
: The authors declare that they have no competing interests.
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