Mao, Chen
Yuan, Jin-Qiu
Lv, Yue-Bin
Gao, Xiang
Yin, Zhao-Xue
Kraus, Virginia Byers
Luo, Jie-Si
Chei, Choy-Lye
Matchar, David Bruce
Zeng, Yi
Shi, Xiao-Ming
Funding for this research was provided by:
National Natural Sciences Foundation of China (71233001, 71490732 and 81573247)
United Nations Fund for Population Activities (2P01AG031719)
Claude D. Pepper Older Americans Independence Centers grant (5P30 AG028716)
Article History
Received: 15 October 2018
Accepted: 21 March 2019
First Online: 15 April 2019
Ethics approval and consent to participate
: All participants signed an informed consent form prior to participation and the study was approved by the Ethics Committee of Peking University and Duke University.
: Not applicable.
: The authors declare that they have no competing interests.
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