Use of identity theories in smoking cessation research: a scoping review

Abstract Introduction The role of identity is increasingly a subject of study in smoking cessation research. However, there is still no standard approach to accounting for the construct of identity in such context. The present review was set to identify theories used in peer-reviewed studies to inform the concept of identity in smoking cessation research. Methods A systematic search strategy containing MeSH-based terms focusing on identity and smoking cessation was applied to three databases on February 15, 2026. Results Thirty-one studies were included using qualitative, survey, experimental, mixed-methods, and software-development designs. Nine theories were used: the Plans, Responses, Impulses, Motives, and Evaluations (PRIME) theory of motivation (n = 11); Theory of Planned Behavior (n = 6) and/or Theory of Reasoned Action (n = 1); Social Identity Theory (n = 7) and/or Self-Categorization Theory (n = 2); Social Identity Threat (n = 4); Symbolic Interaction Theory alone (n = 1) or in combination with Integrative Theory of Identity (n = 1); and Cognitive Dissonance Theory (n = 1). These theories served as theoretical frameworks or foundations for developing hypotheses, guiding data collection and analysis, and conceptualizing identity. Despite differences in methods and outcomes, studies highlight that identity plays an important role in smoking cessation. Conclusions Identified identity theories in smoking cessation research fall broadly into cognitive or social categories, but there is no consistent approach to selecting or operationalizing them. Findings are limited by the number and heterogeneity of studies, but suggest identity is a valuable target for enhancing and developing personalized smoking cessation interventions. Implications This review explores the theoretical frameworks used to operationalize the construct of identity in smoking cessation research. From more cognitive/individual-focused theories to others that pay further attention to the social aspects of the construct of identity, there is a wide range of theories currently used in smoking cessation research. Despite the heterogeneity of design and results, the construct of identity represents a promising target for cessation interventions and further studies. However, it is essential to address inconsistencies in theoretical approaches, paying attention to the interplay between individual, social, and cultural factors that shape identity and its role in smoking cessation.