PROJECT ABSTRACT Successfully increasing cessation rates among African Americans would reduce the racial disparity in mortality between African Americans and Whites by up to 20%. Many smoking cessation interventions include physical activity components to boost cessation rates, but no studies have attempted to promote sedentary behavior reduction as a cessation strategy. Further, smartphones can facilitate intensive behavioral interventions without requiring burdensome in-person treatment, and these interventions can be tailored to address the specific needs of African Americans and capitalize on cultural strengths to reduce barriers and encourage behavior change. Our research team has developed numerous smartphone interventions to address a range of modifiable health risk factors among vulnerable populations, which are capable of being culturally tailored for African Americans. Of relevance to this research proposal, one is a smartphone-based contingency management intervention that provides financial rewards for smoking abstinence after remote verification of smoking status using low-cost portable carbon monoxide monitors and facial recognition software (i.e., PrevailGO). The other is a smartphone-based sedentary reduction intervention that uses wrist-worn activity monitors in combination with smartphone technology to monitor activity in real-time and deliver activity prompts when individuals are engaged in prolonged bouts of sedentary behavior (i.e., SMARTpath). My long-term goal is to improve smoking cessation outcomes among African Americans using evidence-based, culturally tailored smartphone interventions. The overall objectives of this research proposal, which is the next step toward achieving this long-term goal, are to (a) create a smartphone application for smoking cessation (i.e., HealthyCells), which will be achieved by integrating two pre-existing evidence-based smartphone interventions, PrevailGO and SMARTpath, (b) create culturally tailored treatment content (i.e., messages, images, and videos) for African American smokers, and (c) evaluate the feasibility of HealthyCells at addressing smoking and sedentary behavior among African Americans. A pilot sample of African American smokers (N = 15) will briefly use the HealthyCells app and provide critical feedback through semi- structured interviews to refine the smartphone intervention. Once the HealthyCells app is refined, African Americans (N = 30) who are interested in quitting smoking will use the app during a scheduled quit attempt. Starting on the scheduled quit date, HealthyCells will prompt participants to complete twice-daily remote smoking status assessments to earn rewards for abstinence. The app will deliver real-time messages telling participants to stand up and move around during prolonged bouts of sedentary behavior (i.e., ≥ 30 minutes of uninterrupted time spent in a sitting, reclining, or lying posture). Participants will also have on-demand access to culturally tailored information and strategies for remaining abstinent and reducing sedentary behavior within the HealthyCells app. The primary outcomes will be biochemically confirmed point prevalence smoking abstinence at 8 weeks post-quit date, and the difference in sedentary time 7 consecutive days before quitting compared with 7 consecutive days at 8-weeks post-quit, as measured by a research- grade accelerometer.

PROJECT NARRATIVE Successfully increasing cessation rates among African Americans will reduce the racial disparity in mortality among African Americans and Whites by up to 20%. This K01 research proposal outlines, in detail, a plan to develop an evidence-based smartphone intervention for smoking cessation with adjunctive sedentary behavior reduction, which will be culturally tailored for African Americans. Although there are numerous in-person interventions for smoking cessation that have been tailored for African Americans and minorities, smartphone-based interventions are still lacking; thus, this proposal represents an innovative and modern approach for eliminating tobacco-related health disparities in this underserved population.