Text and Data Mining valid from 2018-07-11
Received: 8 September 2017
Accepted: 5 July 2018
First Online: 11 July 2018
Ethics approval and consent to participate
: The study was a retrospective study and was conducted with a waiver of patient consent but approved by the Institution Review Board of the Chang Gung Medical Foundation (No. 201601571B0).
: Not applicable.
: All authors declare that they have no competing interests.
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