Funding for this research was provided by:
Ministry of Education, Culture, Sports, Science and Technology (JP18K17979)
Text and Data Mining valid from 2019-07-05
Received: 17 April 2019
Accepted: 27 June 2019
First Online: 5 July 2019
Ethics approval and consent to participate
: This study protocol was approved by the Medical Ethics Committee of Showa University School of Medicine (Approval No. 2407) and the Ethics Committee of the All Japan Labor Welfare Foundation (Approval No. 9-1-0007). Written informed consent was obtained from each subject.
: Not applicable.
: The authors declare that they have no competing interests.