Funding for this research was provided by:
National Natural Science Foundation of China (31760284)
Article History
Accepted: 27 October 2022
First Online: 10 November 2022
Declarations
:
: This study was approved by the Research Ethics Committee of Nanning Normal University and the principals of the participating kindergartens.
: The authors declare that they have no conflict of interest.
: Informed consent was obtained from all individual participants included in the study.