Text and Data Mining valid from 2018-04-10
Received: 4 August 2017
Accepted: 5 April 2018
First Online: 10 April 2018
Ethics approval and consent to participate
: The Institutional Review Board of Chang Gung Memorial Hospital approved the present study.
: The authors declare that they have no competing interests.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.