Funding for this research was provided by:
Japan Society for the Promotion of Science (JP17K10174, JP15K09707)
Text and Data Mining valid from 2019-11-04
Received: 9 April 2019
Accepted: 21 October 2019
First Online: 4 November 2019
Ethics approval and consent to participate
: The study was approved by the institutional review board of Tokyo Medical and Dental University (no. M2017–337; date: May 8, 2018). The requirement of individual informed consent was waived by the institutional review board because of the retrospective nature of the study and because the data of the involved participants were anonymized.
: Not applicable.
: The authors declare that they have no competing interests.