The long-term goal of this project is to improve Veteran health and longevity by developing and implementing an evidence-based screening strategy to prevent death from second primary lung cancer (SPLC) in lung cancer survivors. This is important because SPLC is distinct from recurrence and is one of the main mortality risks for survivors. Despite its importance, there is no evidence-based standard-of-care for basic questions like which patients to screen for SPLC and for how long. As treatment and screening improve and the number of lung cancer survivors increase, there is a critical need for research into interventions to implement evidence-based cancer screening for cancer survivors. To address this need, we propose to adopt an evidence- based strategy increasingly used in initial primary lung cancer (IPLC) screening, risk stratification. Risk stratification has led to marked improvements in IPLC screening, increasing screening efficiency while also containing ballooning healthcare costs and reducing disparities. To achieve similar improvements for SPLC, our group has developed and validated a predictive model to stratify lung cancer survivors by risk of SPLC, now to be piloted in a clinical setting in this project. Our project is innovative as it is the first (to our knowledge) to implement risk stratification for SPLC. The objective of our proposal is to develop a Veteran-specific and disparity-sensitive clinical decision support tool to stratify Veterans by SPLC risk in clinic. Our central hypotheses are that 1) our model can accurately identify Veterans at high risk for SPLC and 2) identification of high-risk patients is feasible in a VA clinical setting. To accomplish the study objective, the following specific aims will be pursued. Aim 1 will validate and adapt our previously developed SPLC risk prediction model for Veterans, utilizing patient demographics, smoking history, and IPLC treatment, stage and histology derived from the VA EMR. Aim 2 will identify factors that influence feasibility and acceptability of a SPLC risk stratification tool, using a mixed methods approach to focus on provider decision-making and structural or systemic influences at the facility level. Aim 3 will translate the SPLC risk prediction model into a clinical decision support tool and pilot the tool at a single VA site, using iterative cycles to improve tool uptake. Following successful completion of this proposal, the expected research outcomes are to have 1) an updated optimal SPLC risk prediction model for Veterans and 2) a feasible clinical decision support tool based on the model, which a clinician can use to identify patients at high risk of SPLC. In addition, the mentored training program described in this proposal will accelerate Dr. Julie Wu’s development into an independent health services researcher. Her mentorship team includes Drs. Arya, Backhus, and Han- leaders in implementation science, thoracic oncology, and predictive modeling. From this prop...