Evidence suggests that the impact of health warnings and messages that are repeated tends to decrease over time , where as changes in health warnings and messages are associated with increased effectiveness. It is widely accepted that the salience of advertising and health communications is typically greatest upon initial exposure.  For example, a recent study found that new text-based warnings introduced in the United King- dom in 2003 were considerably more likely to be noticed than Australian text-based warnings which were only slightly smaller, but had been in place for more than eight years at the time of the survey.  The frequency with which smokers pay attention to warnings has been shown to lessen over time as smokers become desensitized to the warnings.  As a result, health warnings must be regularly updated to maintain their maximum impact over time.

Current International Best Practice

Several countries have regularly updated their health warnings. Uruguay has rotated sets of warnings four times in the period between 2006 and 2010, while Brazil has implemented three sets of warnings since 2002. In Southeast Asia, Thailand has implemented three sets of health warnings between 2005 and 2010, and Singapore has implemented two. In most cases, new sets of health warnings have been achieved through new regulatory measures. However, countries such as Australia, Mexico and Brunei have implemented a single regulation which stipulates the rotation period for different sets of health warnings in the future. For example, Malaysia has an administrative order that requires a two-year period of rotation, while in Mexico, a set of eight health warnings is to be implemented for the year beginning September 2010 with a second set scheduled for the following year. Moreover, the Mexican regulation requires two health warnings to be released every three months during these periods.

Laws and Regulations

Brunei Tobacco (Labelling ) Regulations 2007
Malaysia Control of Tobacco Product Regulations 2008
Singapore Smoking (Control of Advertisements and Sale of Tobacco) (Labelling) Regulations 2003
Singapore Smoking (Control of Advertisements and Sale of Tobacco) (Labelling) Regulations 2006