Wang, Xiaohong
Xie, Zhen http://orcid.org/0000-0003-0722-5168
Xiong, Shuguang
Xiong, Wei
Zhong, Tian
Su, Yang
Funding for this research was provided by:
Research Foundation of the Sichuan Provincial Health and Family Planning Commission ((17PJ369))
Article History
Received: 4 January 2020
Accepted: 20 April 2020
First Online: 29 April 2020
Ethics approval and consent to participate
: The study protocol complied with the Declaration of Helsinki and was approved by the ethics committee of the Sichuan Provincial People’s Hospital (2017–158). Due to the retrospective nature of the study and because the data were analyzed anonymously, the committee waived the requirement for informed consent.
: Not applicable.
: The authors declare that they have no competing interests.