Li, Yuanyuan
Li, Jihong
Hu, Tong
Hu, Jia
Song, Ning http://orcid.org/0000-0002-9941-0944
Zhang, Yu
Chen, Yuan
Article History
Received: 23 January 2020
Accepted: 5 May 2020
First Online: 3 August 2020
Ethics approval and consent to participate
: The retrospective study was approved by the Ethics Committee of the Second Hospital of Hebei Medical University. Informed consent was waived because this was a retrospectively study.
: Not applicable.
: The authors declare that they have no competing interests.