Article History
Received: 23 December 2019
Accepted: 29 April 2020
First Online: 6 May 2020
Ethics approval and consent to participate
: This study was approved by the Clinical Research Ethics Committee of Kyoto Daini Red Cross Hospital (Approval ID No. 2018–08). The ethics committee waived the requirement for informed consent because of the anonymous nature of the data. We provided a means to opt out in our hospital.
: Not applicable.
: The authors do not have any competing interests related to this manuscript.