PROJECT SUMMARY/ABSTRACT Tobacco is the leading cause of preventable death and disease and is linked to approximately 20 cancers. The rate of decline of tobacco use has been lower for marginalized populations compared to more privileged groups. Most research on tobacco inequities has examined differences based on a single attribute like race/ethnicity, yet this ignores heterogeneity within groups and how multiple aspects of a person’s identity like their race/ethnicity, socioeconomic status (SES), or gender may interact to shape lived experiences and health behaviors. Intersectionality posits that interconnections among multiple aspects of identity and their interaction with social, and contextual factors can contribute to inequities. This framework is useful for shifting focus from broad sectors of the population to groups with disproportionate health risk. Mobile health methodology (mHealth), such as AutoSense and ecological momentary assessment (EMA), provide real-time objective and subjective assessments of how and when emotions and behaviors change depending on time and context and can inform just-in-time adaptive interventions for populations disproportionately affected by tobacco use. The objective of this proposal is to advance methodological and content knowledge of the utility of intersectionality for examining psychosocial, behavioral, and contextual factors that contribute to tobacco use and cancer inequities. Training goals incorporate tobacco use and health inequities, mHealth methodology, advanced statistics, and professional development. The K99 phase will take place at the Huntsman Cancer Institute and focuses on tobacco use and mechanisms of behavior change (e.g., stress, affect, self-efficacy) in intersectional groups using the existing EMA and AutoSense data of the primary mentor, Dr. David Wetter, who is an expert in mHealth, health inequities, and interventions targeting tobacco behavior change. Training with co-mentors Benjamin Haaland in advanced statistics, Dr. Inbal ‘Billie’ Nahum-Shani in behavioral theory and the development of adaptive interventions, and Dr. Nicole Else-Quest in quantitative intersectionality research will contribute to training goals. The R00 phase will consist of a novel intersectionality study using AutoSense and EMA to investigate the real-time dynamics of intersectional identities with stress, negative affect, self-efficacy, and tobacco use in real-time. This work is innovative because no studies to-date have examined tobacco use inequities using an intersectionality framework, nor have any studies combined this framework with the use of cutting-edge technology like AutoSense and EMA to investigate tobacco use inequities in real-time. This work can directly inform tailored interventions targeting tobacco use behaviors among populations at specific sociodemographic intersections that confer inequitable cancer risk and directly addresses the NCI’s mission to conduct and support cancer research to ...