Funding for this research was provided by:
Ministry of Science and Technology, Taiwan (104-2628-H-010-001, 104-2511-S-010-004-MY3)
Text and Data Mining valid from 2018-12-01
Received: 7 March 2018
Accepted: 30 November 2018
First Online: 19 December 2018
Ethics approval and consent to participate
: Data from eight international surveys was used in the present investigation and, in these surveys, written informed consent was obtained at the start of the interviews in all cases. Furthermore, all data was anonymized before use. All procedures performed in this study were reviewed and approved by the Institutional Review Board (IRB) of National Yang-Ming University in Taiwan (IRB number YM103117E-1).
: Not applicable.
: The authors declare that they have no competing interests.
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