Funding for this research was provided by:
Health Promotion Administration, Ministry of Health and Welfare
Ministry of Education, Culture, Sports, Science and Technology
the Japan Agency for Medical Research and Development
Text and Data Mining valid from 2019-08-26
Received: 27 May 2019
Accepted: 19 August 2019
First Online: 26 August 2019
Compliance with ethical standards
: The authors declare that they have no competing interests.
: Ethics approval and consent for each institution to participate in the study was approved by the institutional research ethics committee in accordance with local ethical regulations.
: Informed consent was not required due to the observational and anonymous nature of data collection.