Funding for this research was provided by:
The National Natural Science Foundation of China (NO.71704053)
China Scholarship Council of Chin (NO.201908330251)
Zhejiang Province Natural Science Foundation (NO. LQ17G030002)
Received: 9 August 2019
Accepted: 17 October 2019
First Online: 21 November 2019
Ethics approval and consent to participate
: This study protocol was reviewed by the Chifeng University’s Institutional Review Board, Clinical Trial Committee in addition to the University Medical Ethics Committee. This study was conducted in accordance with the ethical principles of the Declaration of Helsinki. All empty-nest older adults who met the study’s inclusion and exclusion criteria were informed of the study’s objectives, procedures, psychological benefits, and potential risks. Oral and written consent was obtained from the participants, and all information regarding them was kept strictly confidential.
: Not applicable.
: The authors declare that they have no competing interests.