Wang, Yongming
Jing, Lijun
Wang, Gongchao
Article History
Received: 4 March 2020
Accepted: 18 May 2020
First Online: 12 August 2020
Ethics approval and consent to participate
: This study was conducted in accordance with the declaration of Helsinki. This study was approved by the Ethics Committee of the Second People’s Hospital of Weifang. Because this was a retrospective study, informed consent was waived.
: We have obtained consent to publish from the participants (or legal parent or guardian) to report their individual patient data.
: The authors declare that they have no competing interests.