1 Department of General Paediatrics, Willem Alexander Children's Hospital, Leiden University Medical Center, Leiden, Netherlands f.g.ropers@lumc.nl.
2 Sydney School of Public Health, University of Sydney, Sydney, New South Wales.
3 Minneapolis VA Center for Care Delivery and Outcomes Research and the University of Minnesota, Minneapolis, MN, USA.
4 Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Canada.
5 Warwick Medical School, Coventry, UK.
6 Division of Cancer Control and Population Sciences, National Cancer Institute, Bethesda, MD, USA.
7 Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA, USA.
8 Oregon Health and Science University, Portland, OR, USA.
9 Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, UK.
10 School of Medicine, University of North Carolina at Chapel Hill, NC, USA.
11 Australian Centre for Health Engagement, Evidence and Values, University of Wollongong, Wollongong, NSW, Australia.
12 Centre for Evidence-Based Medicine Odense (CEBMO) and Cochrane Denmark, Department of Clinical Research, University of Southern Denmark, Odense, Denmark.