Ethical considerations
For baseline, the study was approved by the Ethics Committee of Faculty of Medicine at the University of Indonesia in September 2014. For endline, the study was approved by the Health Media Lab Institutional Review Board (IRB) in January 2019, the SurveyMETER IRB in December 2018 and the Universitas Atma Jaya IRB in January 2019. Before collecting any data, verbal informed consent was obtained from all respondents.