Article History
Received: 24 November 2020
Accepted: 9 March 2021
First Online: 19 March 2021
Declarations
:
: This study was approved and administrative permissions to access the medical records was granted by the Institutional Review Board of First People’s Hospital of Chenzhou. Consent to participate was waived since this was a retrospective study. Patient-related data used in this study was deidentified before its use. All procedures performed in this study involving human participants conformed to 1964 Helsinki declaration and its later amendments or comparable ethical standards and the ethical standards of the institutional and/or national research committee.
: Not applicable.
: The authors declare that they have no competing interests.