Int. J. Environ. Res. Public Health 2011, 8 425 Variables Low Canada Mod. High All Low All Low Australia Mod. High All Table 3. Cont. United States Mod. High Socioeconomic Status United Kingdom b All Low Mod. High Between Waves among Continuing Smokers Introduce smoke-free 7.8 8.2 4.5 7.1 14.5 16.9 14.9 15.9 64.3 78.1 79.3 74.9 42.2 40.9 48.2 42.8 Retain smoke-free 79.5 81.4 83.9 81.8 36.1 34.6 38.1 35.9 30.3 19.5 17.3 21.7 46.0 46.5 41.1 45.2 Retain smoking 7.2 7.5 10.0 8.2 45.2 45.7 43.5 44.9 4.6 1.8 3.4 2.9 10.5 11.4 9.8 10.9 Remove smoke-free 5.5 2.9 1.6 2.9 4.2 2.8 3.5 3.3 0.8 0.6 0.0 0.5 1.3 1.2 0.9 1.1 n 166 547 310 1,023 166 462 255 883 238 497 208 943 * 239 596 224 1,059 a Percentages are based on weighted data. b A national policy prohibiting smoking in all worksites, restaurants, and bars was implemented between Waves 5 and 6 in three of the four countries that comprise the United Kingdom. The fourth country, Scotland, implemented such a policy prior to Wave 5. * Statistically significant variation across groups (χ2, p < 0.05). Table 4. Prevalence and introduction of smoke-free restaurants by socioeconomic status and country. Variables Wave 5 a Current Smokers Total ban Partial None n Low 90.8 6.7 2.5 294 Canada Mod. High All Low United States Mod. High Socioeconomic Status United Kingdomb All Low Mod. High 90.0 7.0 3.0 842 94.6 4.6 0.8 467 91.5 6.3 2.2 1,603 50.9 27.8 21.3 337 53.2 26.8 20.0 906 58.8 24.5 16.7 429 54.2 26.4 19.4 1,672 34.3 33.4 32.3 380 26.4 36.2 37.4 800 24.0 36.8 39.2 320 All 27.5 35.7 36.8 1,500* Low 81.5 9.1 9.4 363 Australia Mod. High 86.3 7.3 6.4 940 82.5 12.2 6.3 358 All 84.5 8.8 6.7 1,661