Text and Data Mining valid from 2019-06-22
Received: 22 February 2019
Accepted: 17 June 2019
First Online: 22 June 2019
Compliance with ethical standards
: There are no conflicts of interest to declare for any authors.
: All procedure performed in the study involving humans participants were in accordance with the ethical standards of the institutional research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. The study was approved by the Institutional Review Boards of Chung-Ang University Hospital (IRB no. 1600-003-253).
: Informed consent was obtained from all individual participants in the study.