Funding for this research was provided by:
National Natural Science Foundation of China (71473129)
Received: 17 October 2018
Accepted: 28 January 2019
First Online: 6 February 2019
Ethics approval and consent to participate
: As only individual interviews were conducted in this study, it was unnecessary to seek ethics approval for this study according to The Ethical Review Policy of Human Biomedical Research issued by China’s former Ministry of Health [CitationRef removed]. Although no official ethics approval was sought for this study, the research group did follow standard procedures to obtain oral informed consent from each participant.
: Not applicable.
: The authors declare that they have no competing interests.
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