Funding for this research was provided by:
Guangdong Financial Fund for High-Caliber Hospital Construction (NO 174-2018-XMZC-0001-03-0125/-03)
Received: 22 May 2020
Accepted: 10 September 2020
First Online: 16 September 2020
Ethics approval and consent to participate
: This study obtained ethical approval from an ethics committee of Sun Yat-sen University (Number is ERC- -13). Written informed consent was obtained from a parent or guardian of all participants in this study.
: Not applicable.
: We declare that we have no competing interests.