Background: Health warnings on cigarette packages provide smokers with universal access to information on the risks of smoking. However, warnings vary considerably among countries, ranging from graphic depictions of disease on Canadian packages to obscure text warnings in the United States. The current study examined the effectiveness of health warnings on cigarette packages in four countries.
Methods: Quasi-experimental design. Telephone surveys were conducted with representative cohorts of adult smokers (n=14,975): Canada (n=3687), United States (n=4273), UK (n=3634), and Australia (n=3381). Surveys were conducted between 2002 and 2005, before and at three time points following implementation of new package warnings in the UK.
Results: At Wave 1, Canadian smokers reported the highest levels of awareness and impact for health warnings among the four countries, followed by Australian smokers. Following the implementation of new UK warnings at Wave 2, UK smokers reported greater levels of awareness and impact, although Canadian smokers continued to report higher levels of impact after adjusting for the implementation date. U.S. smokers reported the lowest levels of effectiveness for almost every measure recorded at each survey wave.
Conclusions: Large, comprehensive warnings on cigarette packages are more likely to be noticed and rated as effective by smokers. Changes in health warnings are also associated with increased effectiveness. Health warnings on U.S. packages, which were last updated in 1984, were associated with the least effectiveness.