Article History
Received: 11 October 2023
Accepted: 17 April 2024
First Online: 1 May 2024
Competing interests
: The author(s) declare no competing interests.
: This is secondary data analysis. The Beijing Normal University provides the data from the National Children’s Study of China (NCSC). No human beings or animals were involved in this article. The secondary data used was de-identified data. The dataset has been stripped of all identifying information and there is no way it could be linked back to the subjects from whom it was originally collected.
: This article does not contain any studies with human participants performed by any of the authors.
: All authors read and approved the final manuscript.