Funding for this research was provided by:
Foundation of Global Life Learning Center
Received: 20 August 2019
Accepted: 13 October 2019
First Online: 6 November 2019
Ethics approval and consent to participate
: The study protocol was reviewed and approved by the Ethics Committee of the University of Tokyo (Approval Number: 11444). Prior to data collection, all participants will be given information about the study objectives and procedures. Participants will be informed of their right to withdraw from the study at any time or choose not to answer any questions. If they agree to participate, they have to complete and sign an informed consent form. Consistent with best practices for ethical research, this protocol was developed using the SPIRIT guidelines.
: Not applicable.
: The authors declare no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.