Article History
Received: 20 December 2017
Accepted: 27 July 2018
First Online: 6 August 2018
Ethics approval and consent to participate
: This study was approved by the Institutional Review Board of The Catholic Medical Center at the Catholic University of Korea (No. XC14RIMI0013U) on February 1, 2014. We were permitted to access patient medical records in Seoul or Uijeongbu St. Mary’s Hospital at the Catholic University of Korea involved in our study. Informed consent was waived based on IRB guidelines.
: Not applicable.
: The authors declare that they have no competing interests.
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