1. Institute of Clinical Evaluative Sciences; 2075 Bayview Avenue G1 06 Toronto Ontario Canada M4N 3M5
2. Faculty of Health, University of Newcastle; Discipline of Clinical Pharmacology; Level 5, Clinical Sciences Building, Newcastle Mater Hospital Edith Street, Waratah Newcastle New South Wales Australia 2298
3. Faculty of Health, University of Newcastle; Research Centre for Gender, Health & Ageing; Level 5, Clinical Sciences Building, Newcastle Mater Hospital Edith Street, Waratah Newcastle New South Wales Australia 2298
4. Cancer Council; Cancer Epidemiology Research Unit; PO Box 572 Kings Cross Sydney NSW Australia 1340
5. London School of Hygiene & Tropical Medicine; Cochrane Injuries Group; Room 280, North Courtyard Keppel Street London UK WC1E 7HT
6. University of Ottawa Centre for Transfusion Research; Ottawa Health Research Institute; 501 Smyth Road Ottawa Ontario Canada K1H 8L6