Document is current

Article History

Received: 25 November 2019

Accepted: 20 December 2020

First Online: 6 January 2021

Ethics approval and consent to participate

: Written informed consent was informed and obtained from all participants before inclusion in the study. Due to the tight investigation time, the written informed consent of the participants from their parents and guardians was not obtained. However, the written informed consent of the principal of the surveyed school was obtained. The survey plan, questionnaire, participants’ informed consent, informed consent from school leaders instead of informed consent from parents were all reviewed and approved by the Ethics Committee of National Center for Rural Water Supply Technical Guidance, Chinese Center for Disease Control and Prevention.

: Not applicable.

: The authors declare no competing interests.