Funding for this research was provided by:
Project of Introducing Talents of Discipline to Universities of China (B20084)
National Natural Science Foundation of China (71973154, 72074224)
Social Sciences Foundation of Ministry of Education of China (21YJCZH086)
Article History
Received: 21 May 2021
Accepted: 31 August 2021
First Online: 8 September 2021
Declarations
:
: Ethics approval and consent to participate This study is a secondary analysis of the data from the CLHLS. The CLHLS study was approved by the Ethics Committee of Peking University (IRB00001052–13074). The participants provided their written informed consent to participate in this study.
: Not applicable.
: The authors declare no competing interests.