Funding for this research was provided by:
Chang Gung Memorial Hospital, Linkou (CMRPG3G0351)
Received: 7 June 2018
Accepted: 21 August 2018
First Online: 29 August 2018
Ethics approval and consent to participate
: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. This study was approved by the institutional review board of Chung-Gang Memorial Hospital (study reference number: 201701664B0). And the institutional review board granted a waiver of consent for this study.
: Not applicable.
: The authors declare that they have no competing interests.
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