Wang, Meirong
Shao, Shuang
Li, Jing
Liu, Yingjie
Xu, Xiaojingyuan
Funding for this research was provided by:
Capital General Practice Research Project (17QK05)
Article History
Received: 23 August 2018
Accepted: 11 December 2018
First Online: 20 December 2018
Ethics approval and consent to participate
: This study was approved by the Medical Ethics Committee of Capital Medical University, Beijing, China. Written informed consent was obtained from each participant involved in this study. All participant information was kept confidential.
: Not applicable.
: The authors declare that they have no competing interests.
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