Yan, Siyi
Zhang, Huan
Article History
Received: 20 February 2020
Accepted: 6 May 2020
First Online: 24 May 2020
Ethics approval and consent to participate
: The protocol of this study complied with the Helsinki Declaration and was discussed and approved by the ethics committee of the Beijing Tsinghua Chang Gung Hospital. The guardian of each child provided signed informed consent.
: Not applicable.
: The authors declare that they have no competing interests.