Funding for this research was provided by:
Seoul National University Hospital (04-2013-1100)
Text and Data Mining valid from 2019-01-08
Received: 23 December 2018
Accepted: 2 January 2019
First Online: 8 January 2019
Compliance with ethical standards
: The authors report no conflict of interest concerning the materials or methods used in this study or the findings specified in this paper.