Funding for this research was provided by:
Beijing Municipal Administration of Hospitals (XM201410)
Received: 31 January 2020
Accepted: 14 May 2020
First Online: 3 June 2020
Ethical approval and consent to participate
: The protocol was carried out according to GCP guidelines and in accordance with the principles of the Declaration of Helsinki. This study had been approved by the Research Ethical Committee of Beijing Hospital of Traditional Chinese Medicine Affiliated to Capital Medical University on 19 November 2014 (ref: 2014BL-067). All participants had signed written informed consent.
: Not applicable.
: The authors declare that they have no competing interests.