Ethical approval
Ethics committee approval was unnecessary due to the nature of the study.
Author contributions
Conceptualisation: LiXia Zhou
. Formal analysis: Yimin Cao
. Funding acquisition: none
. Investigation: Weixin Meng
. Methodology: retrospective study
. Project administration: LiXia Zhou
. Resources: The Second Hospital of Hebei Medical University
. Software: JianXiong Zheng
. Supervision: Duo Gao and Chengye Zhang
. Validation: Weixin Meng
. Visualisation: LiXia Zhou
. Writing-original draft: Yimin Cao and LiXia Zhou
. Writing – review and editing: LiXia Zhou.
Consent form
Written informed consent was obtained from the patient.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Data availability statement
Data sharing is not applicable to this article as no new data were created or analysed in this study.