1. Researcher, Centre for Health Policy, School of Public Health, University of the Witwatersrand, South Africa
2. Distinguished Professor and South African Chair for Health Policy and Systems Research, Centre for Health Policy, School of Public Health, University of the Witwatersrand, South Africa, and School of Geography and Earth Sciences, McMaster University, Hamilton, Ontario, Canada
3. Associate Professor and Director, Centre for Health Policy, School of Public Health, University of the Witwatersrand, South Africa