Funding for this research was provided by:
Shandong Social Science Planning Grant (19CGLJ01)
Young Backbone Teachers Grant of Binzhou Medical University (201872)
Received: 28 August 2020
Accepted: 17 January 2021
First Online: 26 January 2021
Ethics approval and consent to participate
: The ethical oversight of this study was obtained from the Institutional Review Board of Binzhou Medical University (#2018–47). The Institutional Review Board approved a waiver of signed consent and approved a verbal consent as an alternative given (1) the identifiers included in the medical chart were destroyed (i.e., using coding strategies, like yes or no) when collecting data, and (2) the research involved no more than minimal risk to the subjects.
: Not applicable.
: The authors declare no conflict of interest.