Text and Data Mining valid from 2020-04-14
Received: 13 November 2019
Accepted: 18 March 2020
First Online: 14 April 2020
Ethics approval and consent to participate
: This study was approved by the Ethics Committee of Peking University International Hospital (no. 2018029). All enrolled subjects read information on and understood the purpose of this study and then provided informed consent.
: Not applicable
: The authors declare that they have no competing interests