Funding for this research was provided by:
Chang Gung Medical Foundation (CMRPG5D0111)
Ministry of Science and Technology, Taiwan (104-2320-B-182A-013)
Text and Data Mining valid from 2019-04-03
Received: 27 October 2017
Accepted: 24 March 2019
First Online: 3 April 2019
Ethics approval and consent to participate
: This study was approved by the Institutional Review Board of Chang Gung Memorial Foundation (No.: 103-1259B). The consent was waived by the committee of the Institutional Review Board of Chang Gung Memorial Foundation because the serial number of identification card of each case was well encrypted, and thus the real identity could not be traced back.
: Not applicable.
: The authors declare that they have no competing interests.
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