Funding for this research was provided by:
Japan Society for the Promotion of Science (16K10251 and 17K10331)
Zikei Institute of Psychiatry
Text and Data Mining valid from 2019-04-29
Received: 10 September 2018
Accepted: 27 March 2019
First Online: 29 April 2019
Ethics approval and consent to participate
: This study adhered to the 1975 Helsinki Declaration of Human Rights. The Internal Ethical Committee of the Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences approved this study. We gave all participants written explanations of this research, taking into consideration the cognitive impairment of the participants. After a description of the study, written informed consent was obtained from the subjects who were able to express consent. In addition, written informed consent was obtained from their relatives in all cases.
: Not applicable.
: The authors declare that they have no competing interests.
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