1. Department of Health Services Research; Ministry of Health; 29 Rivka Street 91010 Jerusalem Israel
2. Department of Statistics; The Hebrew University of Jerusalem; Mount Scopus 91905 Jerusalem Israel
3. Biostatistics Unit; Gertner Institute for Epidemiology and Health Policy Research; Tel Hashomer 52161 Israel
4. Department of Health Information; Ministry of Health; 4 Shalom Yehuda Street 93480 Jerusalem Israel