1 Crawford School of Public Policy, Australian National University, Canberra, ACT 2600, Australia; Centre for Health Economics Research and Evaluation, University of Technology Sydney, Sydney, NSW, Australia. Electronic address: thomas.longden@anu.edu.au.
2 Australian National University College of Health and Medicine, Australian National University, Canberra, ACT 2600, Australia.
3 Centre for Health Economics Research and Evaluation, University of Technology Sydney, Sydney, NSW, Australia.