1. Norwegian Knowledge Centre for the Health Services; Oslo Norway
2. Norwegian Knowledge Centre for the Health Services; Prevention, Health Promotion and Organisation Unit; PO Box 7004 St Olavs Plass Oslo Norway 0130
3. Royal Free & University College Medical School; Hampstead Campus London UK NW3 2PF
4. Bradford Royal Infirmary; Bradford Institute for Health Research; Duckworth Lane Bradford W. Yorkshire UK BD9 6RJ
5. Castle Hill Hospital; Cottingham North Humberside UK HU16 5JQ
6. University of Tasmania; Menzies Research Institute Tasmania; MS1, 17 Liverpool Street PO Box 23 Hobart Tasmania Australia 7001