Volume 50 | Number 2 | April 2015

Abstract List

Karen E. Joynt M.D., M.P.H., David C. Chan M.D., M.Sc., Jie Zheng Ph.D., E. John Orav Ph.D., Ashish K. Jha M.D., M.P.H.


To assess the impact of Massachusetts Health Reform () on access, quality, and costs of outpatient care for the already‐insured.

Data Sources/Study Setting

Medicare data from before (2006) and after (2009) implementation.

Study Design

We performed a retrospective difference‐in‐differences analysis of quantity of outpatient visits, proportion of outpatient quality metrics met, and costs of care for Medicare patients with ≥1 chronic disease in 2006 versus 2009. We used the remaining states in New England as controls.

Data Collection/Extraction Methods

We used existing Medicare claims data provided by the Centers for Medicare and Medicaid Services.

Principal Findings

was not associated with a decrease in outpatient visits per year compared to controls (9.4 prereform to 9.6 postreform in vs. 9.4–9.5 in controls,  = .32). Quality of care in improved more than controls for hemoglobin A1c monitoring, mammography, and influenza vaccination, and similarly to controls for diabetic eye examination, colon cancer screening, and pneumococcal vaccination. Average costs for patients in Massachusetts increased from $9,389 to $10,668, versus $8,375 to $9,114 in control states ( < .001).


was not associated with worsening in access or quality of outpatient care for the already‐insured, and it had modest effects on costs. This has implications for other states expanding insurance coverage under the Affordable Care Act.