Yao, Xingchen
Xu, Ziyu
Du, Xinru
Article History
Received: 13 September 2018
Accepted: 24 January 2019
First Online: 11 February 2019
Ethics approval and consent to participate
: Beijing Chao-yang Hospital Human Research Ethics Committee classifies this as a retrospective audit and, as such, does not require ethics submission/approval nor consent to participate.
: Beijing Chao-yang Hospital Human Research Ethics Committee classifies this as a retrospective audit and, as such, does not require consent to publish.
: The authors declare that they have no competing interests.
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