Funding for this research was provided by:
Department of Science and Technology (2008GG30002058)
Received: 3 March 2018
Accepted: 18 October 2018
First Online: 6 November 2018
Ethics approval and consent to participate
: Data collection for all phases of the Confucius Hometown Aging Project was approved by the Ethics Committee at the Jining No. 1 People’s Hospital of Jining Medical University, Shandong, China. Written informed consent was obtained from all participants, or in the case of cognitively impaired persons, from a proxy (usually next-of-kin).
: Not applicable.
: The authors declare that they have no competing interests.
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