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Trombley, Ph.D.

Principal Associate

Matthew Trombley has a Ph.D. in economics with concentrations in health and applied econometric methods. He has extensive experience designing and conducting evaluations for the Center for Medicare & Medicaid Innovation (CMMI), including analyses of historically underserved populations.

Dr. Trombley serves as Abt’s project director for the Oncology Care Model (OCM) evaluation and served as quantitative lead for the ACO (Accountable Care Organization) Investment Model evaluation, as well as the hospital-setting portion of the Health Care Innovation Awards evaluation. He has developed programming quality assurance, data management, and data security plans for multiple CMMI evaluations to uphold Abt’s high standards of data and code management. His research on CMMI models has been published in The New England Journal of Medicine and Health Affairs among other journals, and his appearance on Health Affairs’ “A Health Podyssey” podcast was one of the most listened-to episodes of 2022.


  • Project leadership
  • Value-based care, particularly episode-based payment models and accountable care organizations
  • Econometric methods and secondary data analysis
  • Reporting and disseminating analytic methods and findings
  • Code quality, documentation, and replicability

Key Projects:


  • Trombley MJ, Joneydi R, Buatti LA, Schneider KL, Kummet CM, and Morrall I.  “Impact of the Comprehensive Care for Joint Replacement Model on Patient Reported Outcomes.”  Health Services Research. 2022.
  • Trombley MJ, McWilliams JM, Fout B, Morefield B. “ACO Investment Model Produced Savings, But The Majority Of Participants Exited When Faced With Downside Risk.” Health Affairs. 2022. doi: 10.1377/hlthaff.2020.01819
  • McClellan SR, Trombley MJ, Maughan B, Kahvecioglu DC, Marshall J, Marrufo G, Kummet C, Hassol A. “Patient-Reported Outcomes Among Vulnerable Populations in the Medicare Bundled Payments for Care Improvement (BPCI) initiative.” Medical Care. 2021. doi: 10.1097/MLR.0000000000001644
  • Trombley MJ, Fout B, Brodsky S, McWilliams JM, Nyweide DJ, Morefield B. “Early Effects of an Accountable Care Organization Model for Underserved Areas.” The New England Journal of Medicine. 2019. doi: 10.1056/NEJMsa1816660
  • Trombley MJ, Hassol A, Lloyd JT, Buchman TG,   Marier AF, White A, Colligan E.  “The Effect of Enhanced Critical Care Training and 24/7 Tele-ICU Support on Medicare Spending and Post-Discharge Utilization Patterns.”  Health Services Research. 2017. doi:10.1111/1475-6773.12821
Dr. Matthew Trombley