1. Clalit Research Institute, Chief Physician's Office, Clalit Health Services, Tel Aviv, Israel.
2. Health Policy and Planning, Chief Physician's Office, Clalit Health Services, Tel Aviv, Israel.
3. Epidemiology Department, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
4. Department of Nursing, Faculty of Social Welfare and Health Sciences, University of Haifa, Haifa, Israel.