Health Care Spending, Utilization, and Quality 8 Years into Global Payment

Population-based global payment gives health care providers a spending target for the care of a defined group of patients. We examined changes in spending, utilization, and quality through 8 years of the Alternative Quality Contract (AQC) of Blue Cross Blue Shield (BCBS) of Massachusetts, a population-based payment model that includes financial rewards and penalties (two-sided risk).

Using a difference-in-differences method to analyze data from 2006 through 2016, we compared spending among enrollees whose physician organizations entered the AQC starting in 2009 with spending among privately insured enrollees in control states. We examined quantities of sentinel services using an analogous approach. We then compared process and outcome quality measures with averages in New England and the United States.

During the 8-year post-intervention period from 2009 to 2016, the increase in the average annual medical spending on claims for the enrollees in organizations that entered the AQC in 2009 was $461 lower per enrollee than spending in the control states (P<0.001), an 11.7% relative savings on claims. Savings on claims were driven in the early years by lower prices and in the later years by lower utilization of services, including use of laboratory testing, certain imaging tests, and emergency department visits. Most quality measures of processes and outcomes improved more in the AQC cohorts than they did in New England and the nation in unadjusted analyses. Savings were generally larger among subpopulations that were enrolled longer. Enrollees of organizations that entered the AQC in 2010, 2011, and 2012 had medical claims savings of 11.9%, 6.9%, and 2.3%, respectively, by 2016. The savings for the 2012 cohort were statistically less precise than those for the other cohorts. In the later years of the initial AQC cohorts and across the years of the later-entry cohorts, the savings on claims exceeded incentive payments, which included quality bonuses and providers' share of the savings below spending targets.

During the first 8 years after its introduction, the BCBS population-based payment model was associated with slower growth in medical spending on claims, resulting in savings that over time began to exceed incentive payments. Unadjusted measures of quality under this model were higher than or similar to average regional and national quality measures. (Funded by the National Institutes of Health.).