1. Department of Health Sciences, Buskerud University College, P.O. Box 7053, 3007 Drammen, Norway
2. Department of Behavioral Medicine, Faculty of Medicine, University of Oslo, 0316 Oslo, Norway
3. Department of Family Health Care Nursing, University of California at San Francisco, San Francisco, CA 94143-0606, USA
4. Centre for Clinical Nursing Research, Lovisenberg Deaconal University College, 0456 Oslo, Norway
5. Research Centre and Division of Medicine, Department of Gastroenterology, Oslo University Hospital, 0424 Oslo, Norway