Received: 13 March 2019
Accepted: 20 June 2019
First Online: 25 June 2019
Ethics approval and consent to participate
: Informed consent was omitted and information of this study was disclosed in the form of opt-out on our hospital website. The study has been approved by the Institutional Review Board at the Kochi Medical School Hospital (accepted number: ERB-104180), and was undertaken in accordance with the Helsinki declaration and the Japanese Good Clinical Practice Guidelines.
: Not applicable.
: The authors declare that they have no competing interests.