Funding for this research was provided by:
National Natural Science Foundation of China (71774005)
Article History
Received: 12 August 2019
Accepted: 22 November 2019
First Online: 3 December 2019
Ethics approval and consent to participate
: Since the data obtained from the CHIRA database was de-identified, this study was exempt from Institutional Review Board review by the Ethics Committee of Peking University Health Science Center, Beijing, China (No. IRB00001052–17022).
: Not applicable
: The authors declare that they have no competing interests.