Text and Data Mining valid from 2019-04-04
Received: 9 January 2019
Accepted: 1 April 2019
First Online: 4 April 2019
Compliance with ethical standards
: The authors have no competing interests to declare.
: Ethical approval was obtained from Institutional Review Board of Sakai City Medical Hospital. Consent to participate was not applicable owing to the retrospective nature of the study.
: Not applicable.
: All data generated or analyzed during this study are included in this published article.