PROJECT SUMMARY/ABSTRACT Lung cancer is the leading cause of cancer death in the United States, and lung cancer screening (LCS) has been demonstrated to effectively reduce lung cancer mortality by 20-26% in eligible people. Despite 10 years of recommendations endorsing screening, evidence suggests that real-world implementation of LCS has been poor: Only 5-20% of all eligible patients have received guideline-concordant LCS. Studies reveal that uptake of screening is even lower among racial and ethnic minoritized communities and those who face barriers related to social determinants of health. American Indian and Alaska Native (AI/AN) people have both the highest prevalence of commercial tobacco smoking of any racial or ethnic group in the United States, and are the most likely to meet eligibility criteria for screening. Despite this, there is almost no research on culturally-adapted and effective interventions to support LCS in this population. Patient navigation appears to be a promising intervention to enhance LCS care completion in underserved patient populations. Patient navigation represent services delivered by a patient navigator to overcome barriers and support the timely completion of recommended healthcare along a care continuum. Navigation appears to be effective in underserved patient populations, and in randomized trials, may improve the likelihood of completing LCS by up to 4-fold. Navigation may be a valuable approach in AI/AN communities; however it is critical that this strategy is adapted to and evaluated in AI/AN community healthcare settings. In prior partnership with a Tribal Epidemiology Center, we developed and piloted an approach to LCS navigation by and for AI/AN people at-risk for lung cancer. The central objective of this proposal is to locally adapt and comprehensively evaluating the effectiveness and implementation of this navigation intervention in partnership with Western Washington state tribal groups spanning mixed rural-urban areas through a pragmatic hybrid effectiveness-implementation trial. In the first aim, we will systematically adapt the intervention to local settings and evaluate the impact of a navigation approach on completion of LCS through a randomized controlled trial. In the second aim, we will use a mixed-methods approach to assess the barriers and facilitators to navigation engagement and LCS care completion. Finally in the third aim, we will evaluate the maintenance and sustainability of the navigation intervention after the clinical trial. The aims will span the dimensions of the Exploration, Preparation, Implementation, and Sustainment (EPIS) Framework and will be grounded in an integration of the Consolidative Framework for Implementation Research and an NIH-developed health disparities framework tailored for AI/AN communities. Our team has extensive experience in LCS implementation and disparities with expertise in adapting and evaluating pragmatic interventions in community settings. This pro...