In 2000, Canada became the first country to mandate large graphic pictorial warnings on cigarette packs. Each design was composed of; a general warning theme, text-based information, a picture, and self-efficacy oriented health messages [1,2]. Since Canada first adopted its graphic pack warnings, many other countries have done the same [2–7]. The number of countries adopting graphic warnings is increasing (see http://www.tobaccolabels.ca/healthwarnings for the latest number).

Several published studies, mostly conducted in high income countries, have confirmed the superiority of graphic pack warnings compared to text-based warnings in informing the public about the risks of smoking and stimulating interesting in quitting smoking [6,8–12]. Risk perception has been found to be affected by socioeconomic factors, among which are education and income [13]. This highlights the importance of studying the effect of cigarette warning labels in middle- and low-income countries to ascertain either universality or diversity of the impact of such warnings across countries with different levels of access to knowledge. A study in Mexico, a middle income country, found that smokers respond to warnings in a similar way to smokers in high income countries [14]. In the same context, Fathelrahman and associates [15] showed that Malaysian smokers responded to textural warnings in a fashion comparable to that identified in the West, so we might expect a high degree of generalization. However, it is important to test this hypothesis and also very useful to see if reactions to isolated exposures mirror those to repeated exposures as happens once warnings are introduced.

Figure 1 shows the standard pack warning on cigarettes sold in Malaysia before January 2009. The single text-only message stated: “warning by the Malaysian government; smoking is hazardous to health”. Malaysia ratified the World Health Organization’s Framework Convention on Tobacco Control in September 2005, which obligated them to adopt an enhanced tobacco product warning system [16]. Malaysia, like many other countries, adopted a rotating series of graphic pictorial warnings labels beginning in January 2009.

This paper presents results from an evaluation undertaken study just prior to the appearance of the new graphic warnings on cigarette packs to gauge how the new warnings might impact awareness of the health risks of smoking, response to the package warnings, and interest in quitting smoking among a sample of Malaysian adult current smokers.

This study demonstrates that the new Malaysian health warnings will have beneficial effects on knowledge and concerns about the harms of smoking and interest in quitting, at least in the short term. These findings are consistent with previous studies showing the benefits of large pictorial cigarette pack warnings over text-based warnings in high income countries [11,12,17] and another middleincome country [14]. The main strength of this study is that it was a randomized trial, thus demonstrating a causal relationship between exposure to the warnings and the changes in knowledge and smoking-related concerns. The main limitations are that we only assessed immediate reactions, and only assessed the pictorial warnings as a group. This means we cannot say anything about longer term effects, or on the specific effects of particular warnings, except for relevant knowledge increases. We also note that, in some cases, we used questions that covered a longer period, but it is clear from the mode of responding that participants took it to mean what they expected they would do, rather than what they did do. The sample used here was also a convenience sample, not representative of smokers in Malaysia. Nevertheless, there was nothing special about the sample to suggest that their reactions would systematically differ to reactions of other Malaysian smokers.

The finding of knowledge increases across most of the health effects is consistent with respondents taking in the information that was provided. Those with no significant increases were ones with very high baseline levels, and the small increases were not significant. One item, on asthma, was not a headline health effect, but was mentioned in the supplementary text to the headline warning “warning: tobacco smoke harms children”, suggesting that respondents read at least some of the detailed information.

When considered in conjunction with the findings of population-based studies of representative samples from other countries which show long term predictive effects, we can conclude that this research strengthens the argument that these population-wide effects are causal, and that the same kinds of long term beneficial effects of the new warnings found elsewhere are likely to occur in Malaysia. Graphic health warnings both can improve public knowledge, and work to encourage cessation through the generation of concern stimulated by the emotionally charged messages. The value of graphic warnings is that they make the potential of smoking to cause disease more real to the smoker, and thus are better at stimulating them to think about acting to avoid this risk. In this regard, it is important to point out that the increase in reported avoidance of warnings found here is a positive, not a negative, predictor of subsequent quitting [12].

Analog studies of the kind used here can be used to predict likely impact of warnings when implemented, given that they mirror population-level effects of prolonged exposure. Coupled with the existing evidence, this study demonstrates that the new Malaysian warnings are likely to lead to better knowledge of health effects of smoking [17], and will lead to more of the reactions to warnings that have been prospectively shown to predict making quit attempts [11,12].