Funding for this research was provided by:
national natural science foundation of china (No. 81703249)
shanghai municipal population and family planning commission (201640297)
biostime nutrition and care of maternal & child research funding program (No.2017BINCMCF12)
Received: 30 July 2021
Accepted: 26 November 2021
First Online: 13 December 2021
: The Institutional Review Board and the Committee on Research Involving Human Subjects of Xinhua Hospital, which is affiliated with Shanghai Jiao Tong University, approved the survey (reference number: XHEC-C-2017-144), and the research was carried out in compliance with the Declaration of Helsinki. All participant's parents provided written consent prior to participate in the survey.
: We have reviewed the final version of the manuscript and approve it for publication.
: The authors have no conflicts of interest.