Funding for this research was provided by:
National Health Insurance Service (NHIMC2017CR001)
Article History
Received: 1 February 2018
Accepted: 25 May 2018
First Online: 1 June 2018
Ethics approval and consent to participate
: This study was approved by the institutional review board of the National Health Insurance Service Ilsan Hospital (NHIMC IRB 2017–02-003). As it was a retrospective study with the review of electronic medical record without revealing the patient’s private information, the informed consent was waived.
: The authors declare that they have no competing interests.
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