Received: 21 November 2018
Accepted: 14 March 2019
First Online: 18 March 2019
Ethics approval and consent to participate
: The research was approved by the Institutional Review Board of Taipei Veterans General Hospital. Written informed consent to participate in the study was obtained from all participants in the present study.
: Written consent for publication was obtained from participants to publish potentially identifying details.
: The authors declare that they have no competing interests.
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