Article History
Received: 26 July 2018
Revised: 2 December 2019
Accepted: 9 January 2020
First Online: 16 January 2020
Compliance with ethical standards
:
: Megumi Shimada, Makoto Akaishi, and Takayuki Kobayashi declare that they have no conflicts of interest.
: All procedures followed were in accordance with the ethical standards of the responsible committee on human experimentation (institutional and national) and with the Helsinki Declaration of 1964 and later revisions. This study was approved by the clinical trial review committee of the Kitasato Institute Hospital (No. 17082). Opt-out consent was used because this was a retrospective study.