1. Norwegian Knowledge Centre for Health Services; PO Box 7004 St Olavs Plass Oslo Norway 0130
2. University of Western Ontario; Faculty of Health Sciences; London Ontario Canada
3. University of Western Ontario; Health and Rehabilitation Science, Elborn College; London Ontario Canada N6G 1H1
4. Norwegian Knowledge Centre for the Health Services; P.O. Box 7004, St. Olavs plass Oslo Norway N-0130