As demonstrated previously by Li et al. (2011), the greater such nicotine dependency would make it harder to quit smoking. Thus, it is not surprising that this group has lower confidence in being able to quit and have lower interest in quitting their habits. The lower quitting self-efficacy and quitting interest may also arise from social factors such as the levels of support for quitting and social pressure to quit smoking from friends and family members. For example, blue-collar workers, compared with other workers, have been found to experience less social pressure to quit and less social support for quitting (Sorensen, Emmons, Stoddard, Linnan, & Avrunin, 2002).

In fact, there is some recent evidence from a small exploratory study conducted from a Guangzhou hospital smoking cessation clinic in China to suggest that the social-cultural context of Chinese smokers where cigarettes are commonly given as a gift and the widespread misconception about quitting being harmful to health may make it even more challenging for them to quit smoking (Zhang, Chan, Fong, Malone, & Lam, 2011). It is possible that low SES smokers may be more susceptible to this kind of social-cultural pressure than those from higher SES groups, something that awaits future research. It may also be the case that low SES smokers have low self-confidence in quitting because they have less access to smoking cessation aids and resources to help them quit due to cost factors (Murray, Bauld, Hackshaw, & McNeil, 2009).

This study demonstrates that factors such as nicotine dependency, interest in quitting, and self-efficacy are serving as mediators through which SES exerts its influence on quitting behavior among Chinese smokers particularly for quitting initiation. According to Zhao et al. (2010), this is a case of an indirect-only mediation as there is no evidence of a direct effect of SES on quitting behavior suggesting that SES is merely a distal predictor of quitting behavior. In other words, socio-economic disadvantage poses few direct barriers to smoking cessation for urban Chinese smokers. What appears to be the case is that urban Chinese smokers from lower SES backgrounds tend to be more addicted, have lower self-efficacy and lower interest in quitting, and characteristics that are associated with lower likelihood of making a quit attempt.

Even when they try to quit smoking, being more addicted makes it harder to sustain abstinence. These findings suggest that smokers from lower SES groups need not Brefeldin_A only additional help to overcome the initial barriers to quitting but also after they have quit, they need help to overcome the risks of relapsing because of their higher nicotine dependency. It is unclear at this stage what form of help is best for smokers in China. Yang et al.