Text and Data Mining valid from 2019-08-14
Received: 4 May 2019
Accepted: 2 August 2019
First Online: 14 August 2019
Ethics approval and consent to participate
: All participants provided written informed consent according to the Declaration of Helsinki, and the study was approved by the ethics committee of Seoul St. Mary’s Hospital (study number KC15OISI0012).
: Not applicable.
: The authors declare that they have no competing interests.