Although accountable care organization (ACO) attribution and patient engagement often begin with primary care physicians (PCPs), specialists can manage a large portion of the utilization and spending that ultimately determines ACO performance. Specialists influence procedure selection, site-of-service, diagnostic intensity, longitudinal disease management, and downstream utilization across both facility and professional settings.
This dynamic creates an important strategic question for ACOs. If specialists drive a meaningful share of risk-adjusted spending, and if there is material variation in cost efficiency across specialists within a market, can an ACO generate measurable savings through effective management of specialty care? Specifically, can ACOs first establish systems to identify patterns in specialty care, manage referrals, and partner with specialists with a track record of high quality and efficient care? Yes, but only if the data is compelling and a partnership is operationally feasible.
In this case study, we use data from Milliman ACO Builder to demonstrate an analytical framework that ACOs could use. With the Specialist Explorer tool in ACO Builder, users can benchmark specialist performance on 26 episodes of care under the Merit-based Incentive Payment System (MIPS) from the Centers for Medicare and Medicaid Services. To illustrate key concepts in detail, we also focus on cardiology procedures of non-emergent coronary artery bypass grafts, and inpatient and outpatient percutaneous coronary interventions (PCIs).
Key discussion points of this paper include the following:
- Building the analytic foundation: The observed-to-expected efficiency score as a starting point.
- Benchmarking specialty performance and selecting ACO participants: The maximized regional efficiency and historical high-opportunity approaches.
- Building a preferred referral network: Focus on cost efficiency, geographic access, quality of care, and capacity to absorb redirected referrals.
- Going beyond quality metrics: Other essential considerations for ACOs.