1. Research and Development, Australian Red Cross Lifeblood, West Melbourne, Australia
2. School of Global and Population Health, University of Melbourne, Melbourne, Australia
3. Faculty of Social Sciences and Business Studies, University of Eastern Finland, Helsinki, Finland
4. Finnish Red Cross Blood Service, Helsinki, Finland
5. The University of Queensland, Brisbane, Australia
6. National Institute for Health and Care Research Blood and Transplant Research Unit in Donor Health and Behaviour, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK