Relationship between constituent labelling and reporting of tar yields among smokers in four countries.

Countries have adopted different approaches to disseminating cigarette tar, nicotine, and carbon monoxide (CO) levels to consumers, with some (e.g. EU member states, Canada, Australia, but not the United States) requiring disclosure of results from the International Organization for Standardization (ISO) test method on packs. Cross-country comparisons can provide insight into how smokers use yields when information is presented differently. We examined whether smokers in four different countries could recall the tar yield of their brand of cigarettes, using data from the third wave of the International Tobacco Control Four Country Survey (ITC-4). Of current smokers in the United States, Canada, Australia and the United Kingdom, 33.6% gave a numeric response when asked to report the tar yield of their brand, whereas 66.4% responded 'I don't know.' American participants (9.2%) were less likely than Canadian (28.0%), UK (36.5%) or Australian (68.2%) smokers to give an answer, even after controlling for sociodemographic and smoking behaviour factors. Constituent labelling policies can affect whether smokers report a tar yield for their cigarette brand. Pack labelling appears to be useful for conveying information about cigarettes to smokers; however, there is an urgent need to develop more meaningful information on toxic constituents of cigarette smoke.