INTRODUCTION: Mobile mammography (MM) can reach women who otherwise would not or could not utilize facility-based mammography (FBM) due to various socioeconomic factors and access barriers. Most literature evaluates individual MM programs and has not explored the potential impact of MM in a large, nationally representative, claims dataset. OBJECTIVE: To examine factors associated with MM utilization among female Medicare beneficiaries and whether MM is associated with increased mammography utilization compared use of FBM only. MATERIALS AND METHODS: This retrospective analysis of Centers for Medicare & Medicaid Services (CMS) 5% Research Identifiable File data from years 2004 to 2021 used logistic regression to assess likelihood of receiving MM compared with FBM. Linear regression assessed factors associated with decreased mammography utilization. Heat maps demonstrated the geographic density of MM use compared with FBM-only use. RESULTS: Among 2,630,670 screening eligible women, 1,302,069 (49.5%) had a mammogram, of which 4,973 (0.4%) used MM. MM use was associated with age from 50 to 64 years, American Indians or Alaska Natives, fewer comorbidities, rural geography, residence in the West, and lower community income. On multivariate regression, American Indian or Alaska Native race was most predictive of MM (odds ratio 5.53
95CI 4.73-6.47). Heat maps showed that areas of MM usage overlap areas of FBM-only usage. CONCLUSION: Our results suggest MM is utilized by traditionally underserved beneficiaries (ie, non-White in less economically resourced areas), but it is not a replacement for FBM. MM is an augmentative service, potentially offering screening mammography to women who may not have otherwise been screened due to access issues stemming from socioeconomic, geographic, or cultural barriers.