Text and Data Mining valid from 2018-10-19
Received: 2 September 2017
Accepted: 8 October 2018
First Online: 19 October 2018
Ethics approval and consent to participate
: This study was conducted with a waiver of patient consent approved by the Institutional Review Board of Chang Gung Memorial Hospital (Document no. 100-2661B).
: Not applicable.
: The authors declare that they have no competing interests.
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