Text and Data Mining valid from 2018-05-16
Received: 29 April 2017
Accepted: 8 May 2018
First Online: 16 May 2018
Ethics approval and consent to participate
: Institutional review board (IRB) of Kaohsiung General Veterans Hospital approved this retrospective study, where the need of informed consent to participate was waived. The committee’s reference number is VGHKS17-CT5-02.
: The authors declare that they have no competing interests.
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