Gu, Hai
Kou, Yun
You, Hua http://orcid.org/0000-0002-0004-0470
Xu, Xinpeng
Yang, Nichao
Liu, Jing
Liu, Xiyan
Gu, Jinghong
Li, Xiaolu
Funding for this research was provided by:
the National Natural Science Foundation of China (71573118)
Top-notch Academic Programs Project of Jiangsu Higher Education Institutions, TAPP (PPZY2015A067)
Article History
Received: 30 August 2018
Accepted: 1 January 2019
First Online: 8 January 2019
Ethics approval and consent to participate
: Ethical approval for this study was not required because it was based exclusively on the publicly available data, CHARLS, and the study subjects were not directly approached.
: No applicable.
: The authors declare no conflict of interest.
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