The association between exposure to point-of-sale anti-smoking warnings and smokers' interest in quitting and quit attempts: findings from the International Tobacco Control Four Country Survey

AIMS: This study aimed to examine the associations between reported exposure to anti-smoking warnings at the point-of-sale (POS) and smokers' interest in quitting and their subsequent quit attempts by comparing reactions in Australia where warnings are prominent to smokers in other countries. DESIGN: A prospective multi-country cohort design was employed. SETTING: Australia, Canada, the United Kingdom and the United States. PARTICIPANTS: A total of 21,613 adult smokers who completed at least one of the seven waves (2002-08) of the International Tobacco Control Four Country Survey were included in the analysis. MEASUREMENTS: Reported exposure to POS anti-smoking warnings and smokers' interest in quitting at the same wave and quit attempts over the following year. FINDINGS: Compared to smokers in Canada, the United Kingdom and the United States, Australian smokers reported higher levels of awareness of POS anti-smoking warnings, and this difference was consistent over the study period. Over waves in Australia (but not in the other three countries) there was a significantly positive association between reported exposure to POS anti-smoking warnings and interest in quitting [adjusted odds ratio = 1.139, 95% confidence interval (CI) 1.039-1.249, P < 0.01] and prospective quit attempts (adjusted odds ratio = 1.216, 95% CI 1.114-1.327, P < 0.001) when controlling for demographics, smoking characteristics, overall salience of anti-smoking information and awareness of anti-smoking material from channels other than POS. CONCLUSIONS: Point-of-sale health warnings about tobacco are more prominent in Australia than the United Kingdom, the United States or Canada and appear to act as a prompt to quitting.