Funding for this research was provided by:
National Institute on Aging (K07AG043587)
Received: 10 September 2018
Accepted: 14 January 2019
First Online: 1 February 2019
Ethics approval and consent to participate
: The Research Ethics Committees of Peking University and Duke University granted approval for the Protection of Human Subjects for the CLHLS. The current study was approved by the Human Investigation Committee at Yale University [IRB Protocol ID: 2000022449]).
: Not applicable.
: The authors declare that they have no competing interests.
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