Early Performance in Medicaid Accountable Care Organizations: A Comparison of Oregon and Colorado
A variety of state Medicaid reforms are underway, but the relative performance of different approaches is unclear.
To compare performance in Oregon’s and Colorado’s Medicaid Accountable Care Organization (ACO) models.
DESIGN, SETTINGS, AND PARTICIPANTS
Oregon initiated its Medicaid transformation in 2012, supported by a $1.9 billion federal investment, moving the majority of Medicaid enrollees into sixteen Coordinated Care Organizations (CCOs), which managed care within a global budget. Colorado initiated its Medicaid Accountable Care Collaborative (ACC) in 2011, creating seven Regional Care Collaborative Organizations that received funding to coordinate care with providers and connect Medicaid enrollees with community services. We analyzed data spanning July 1, 2010 through December 31, 2014, (18 months pre-intervention and 24 months post intervention, treating 2012 as a transition year) for 452,371 Oregon and 330,511 Colorado Medicaid enrollees, assessing changes in outcomes using difference-in-differences analyses.
Both states emphasized a regional focus, primary care homes, and care coordination. Oregon’s CCO model was more comprehensive in its reform goals and in the imposition of downside financial risk.
Main Outcomes and Measures
Performance on claims-based measures of standardized expenditures and utilization for selected services, access, preventable hospitalizations, and appropriateness of care.
Standardized expenditures for selected services declined in both states over the 2010–2014 time period, but these decreases were not significantly different between the two states. Oregon’s model was associated with reductions in emergency department visits (−6.28 per 1000 beneficiary months, 95% CI −10.51 to −2.05) and primary care visits (−15.09 visits per 1000 beneficiary months, 95% CI −26.57 to −3.61), improvements in acute preventable hospital admissions, three out of four measures of access, and one out of four measures of appropriateness of care.
Conclusions and Relevance
Two years into implementation, Oregon and Colorado’s Medicaid ACO models exhibited similar performance on standardized expenditures for selected services. Oregon’s model, marked by a large federal investment and movement to global budgets, was associated with improvements in some measures of utilization, access and quality, but Colorado’s model paralleled Oregon on a number of other metrics.