This project is part of AcademyHealth’s efforts to better understand and address disparities in diagnosis with funding from the Gordon and Betty Moore Foundation. The goal of this project is to lay the foundation for interventions that reduce disparities in the diagnosis of hypertrophic cardiomyopathy (HCM). HCM is the most common inherited cardiac condition, yet it remains significantly underdiagnosed. This study, guided by the Anderson Model of Total Patient Delay, will identify actionable clinician and system-level targets for intervention that can improve clinician evaluation and decision making related to HCM, and develop pathways to address system-level gaps in HCM evaluation, referral and treatment. The project will use a convergent mixed-methods design to achieve multiple aims: 1) to qualitatively examine clinician-level factors that influence provider assessment; 2) to examine system-level barriers and facilitators to HCM assessment; and 3) to identify targets for intervention to improve diagnostic equity in HCM. The project team will collaborate with community partners, the Hypertrophic Cardiomyopathy Association (HCMA) during the study, including in the development of the clinician interview guide and in study dissemination efforts. Researchers will recruit primary care providers from a large medical system and conduct semi-structured interviews, which will include questions related to decisional factors on HCM evaluation, diagnosis, and referrals, as well as short clinical scenarios of individuals presenting with HCM-related symptoms. Data will be analyzed via content thematic analysis. System-level factors will be examined via analysis of electronic health records data related to key guideline-recommended evaluation and treatment outcomes for adults with HCM. Qualitative and quantitative data will be eventually merged to identify actionable strategies for improvement along the HCM diagnostic pathway to reduce inequities. Merged data will also be used to map out an HCM-specific adaptation of Anderson’s conceptual model. Deliverables will include a project work plan, narrative and financial reports, and a range of products to reach clinicians, policymakers and other audiences for study findings.