1 Department of Medical Ethics and Health Policy, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Center for Health Incentives and Behavioral Economics, University of Pennsylvania, Philadelphia PA, USA; Health Economics and Epidemiology Research Office, Faculty of Health Sciences, University of Witwatersrand, Johannesburg, South Africa. Electronic address: hthirumu@upenn.edu.
2 Center for Health Incentives and Behavioral Economics, University of Pennsylvania, Philadelphia PA, USA; Department of Family and Community Health, School of Nursing, University of Pennsylvania, Philadelphia PA, USA; Health Economics and Epidemiology Research Office, Faculty of Health Sciences, University of Witwatersrand, Johannesburg, South Africa.
3 Health Economics and Epidemiology Research Office, Faculty of Health Sciences, University of Witwatersrand, Johannesburg, South Africa.