Received: 24 May 2021
Accepted: 25 February 2022
First Online: 22 March 2022
: The “National Internal Migrant Dynamic Monitoring Survey, 2017” data is publicly available to authorized researchers who have been given permission by the Migrant Population Service Center. Written informed consents were obtained from all participants. The analysis of public access data was exempted by the Medical Ethics Committee of Tongji University. As this study involved analyzing anonymized existing data, ethical approval was not required.
: Not applicable.
: No competing interests in this study.