Funding for this research was provided by:
This study is funded by Directorate General of Higher Education (DIKTI) Scholarship, Indonesia
Text and Data Mining valid from 2019-01-11
Received: 25 April 2018
Accepted: 3 January 2019
First Online: 11 January 2019
Ethics approval and consent to participate
: The study protocol was approved by the Committee on Ethics Universitas Gadjah Mada, Yogyakarta Indonesia (KE/FK/1108/EC/2016). All study participants gave written informed consent.
: Not applicable
: The authors declared that they have no competing interests.
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