Text and Data Mining valid from 2018-04-16
Received: 29 January 2018
Accepted: 11 April 2018
First Online: 16 April 2018
Ethics approval and consent to participate
: This study was reviewed and approved by the Institutional Review Board of Mackay Memorial Hospital, Taipei, Taiwan (IRB approval number: 17MMHIS022e) and waved to inform the consent by the Institutional Review Board because of retrospective study nature.
: All authors declare no conflict of interests.
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