Funding for this research was provided by:
National Key R&D Program of China (2016YFC1000303)
Guangzhou City Science and Technology Administration (201804020057)
Lin He's Academician Workstation of New Medicine and Clinical Translation at The Third Affiliated Hospital (N/A)
Received: 6 August 2019
Accepted: 29 November 2019
First Online: 7 December 2019
Ethics approval and consent to participate
: This study was approved by the ethics committee of The Third Affiliated Hospital of Guangzhou Medical University [2017(No.128)], and all the procedures have been approved by the ethics committee. Consent to participate was collected from the parents of school students who were informed about this study at the parent-teacher conference, using posters and SMS notification. Because this study was online health survey, only verbal consents were obtained.
: The authors declare that they have no competing interests.