Funding for this research was provided by:
Kementerian Riset, Teknologi dan Pendidikan Tinggi (PTUPT (1818/UNI/DITLIT/DIT-LIT/LT/2018) and PPUPT (1987/2018))
Received: 18 July 2018
Accepted: 23 January 2019
First Online: 6 February 2019
Ethics approval and consent to participate
: The study was approved by the Medical and Health Research Ethics Committee of the Faculty of Medicine Public Health and Nursing, Universitas Gadjah Mada Indonesia (601/EC/2014 and 1143/EC/2017). All participants gave written informed consent prior to participating in this study.
: Not applicable.
: All authors declare that they have no competing interests.
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