Text and Data Mining valid from 2019-11-04
Received: 31 July 2019
Accepted: 25 October 2019
First Online: 4 November 2019
Compliance with ethical standards
: All authors certify that they have no affiliations with or involvement in any organization or entity with any financial interest, or non-financial interest in the subject matter or materials discussed in this manuscript. Joji Inamasu declares that he has no conflict of interest. Masashi Nakatsukasa declares that he has no conflict of interest.
: The study design was approved by Saiseikai Utsunomiya Hospital Institutional Review Board (17-0013). The study was conducted in accordance with the ethical standards laid down in the 1964 Declaration of Helsinki.
: Our IRB determined that written consent from each subject was not necessary.