Funding for this research was provided by:
Beijing Municipal Natural Science Foundation (7162106)
National Natural Science Foundation of China (81573170)
Text and Data Mining valid from 2018-05-03
Received: 14 February 2018
Accepted: 18 April 2018
First Online: 3 May 2018
Ethics approval and consent to participate
: Both the ALIR study and CPOOA study were approved by the Ethics Committee of Peking University Health Science Center. Written informed consent was provided by all participants and, in the case of minors, their parents. Studies were performed according to the Declaration of Helsinki.
: Written informed consent was provided by all participants and, in the case of minors, their parents.
: The authors declare that they have no competing interests.
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