Received: 2 March 2020
Accepted: 8 June 2020
First Online: 13 June 2020
Ethics approval and consent to participate
: This study was approved by the Ethics Committee of the Fifth Affiliated Hospital of Guangzhou. The participant consent was written and was performed in accordance with the ethical standards of the Declaration of Helsinki of 1964.
: Not applicable.
: All authors declare that they have no competing interests.