Beyond Quit Intention: Implicit–Explicit Attitude Profiles, Uncertainty Stress, and Stage-Based Smoking Cessation Status Among Chinese Young Adult Smokers

Background: Smoking behaviour change is commonly conceptualized as a stage-based process, yet stage-based cessation status, quit intention, and cessation action may be associated with psychological factors beyond self-reported motivation. Dual-attitude theory suggests that implicit and explicit attitudes may jointly relate to smoking behaviour, while uncertainty stress may further influence these associations. This study examined the associations of implicit–explicit attitude profiles with smoking behaviour change and the moderating role of uncertainty stress among young adult smokers. Methods: We conducted a cross-sectional secondary analysis of 292 Chinese smokers aged 18–35 years from a source sample of 659 adult smokers. Participants were classified into four implicit–explicit attitude profiles based on SC-IAT and self-reported attitudes. Ordered and binary logistic regression models examined associations of attitude profiles with stage-based cessation status, quit intention, and cessation action, adjusting for sociodemographic characteristics. Uncertainty stress was examined as a moderator. Results: Compared with the consistent positive profile, the consistent negative profile was associated with higher odds of being at a later stage of behaviour change (OR = 6.02, 95% CI 2.78–13.03), having quit intention (OR = 5.27, 95% CI 2.08–13.31), and reporting cessation action (OR = 6.75, 95% CI 2.37–19.47). The implicit positive-explicit negative profile showed similar associations with stage of behaviour change (OR = 4.78, 95% CI 2.13–10.70), quit intention (OR = 5.81, 95% CI 2.09–16.12), and cessation action (OR = 3.96, 95% CI 1.31–11.94). Higher uncertainty stress was associated with greater odds of behaviour change, while interactions between uncertainty stress and attitude profiles indicated smaller differences between profiles at higher stress levels. Conclusions: Implicit–explicit attitude profiles were differentially associated with stage-based cessation status, quit intention, and cessation action, and these associations varied by uncertainty stress. Assessing both implicit and explicit attitudes alongside psychological stress may provide a broader basis for understanding individual differences in smoking behaviour change among young adult smokers.