Funding for this research was provided by:
General Guidance Project of Guangzhou Municipal Health Commission (20191A011023)
Article History
Received: 9 September 2020
Accepted: 26 December 2020
First Online: 11 January 2021
Ethics approval and consent to participate
: The institutional review board of Guangzhou Women and Children’s Medical Center approved the collection and use of clinical information for research purposes (NO46001, 2020; Approval date, January 3, 2020). All information collected from participants during the study was kept confidential. Patients’ consents were not required because this was a retrospective study.
: Not applicable.
: The authors have no conflicts of interest to report. Completed disclosures of interest forms are available to view online as supporting information.