Accountable Care Organizations: The National Landscape

Abstract

There are now more than seven hundred accountable care organizations (ACOs) in the United States. This article describes some of their most salient characteristics including the number and types of contracts involved, organizational structures, the scope of services offered, care management capabilities, and the development of a three-category taxonomy that can be used to target technical assistance efforts and to examine performance. The current evidence on the performance of ACOs is reviewed. Since California has the largest number of ACOs (N=67) and a history of providing care under risk-bearing contracts, some additional assessments of quality and patient experience are made between California ACOs and non-ACO provider organizations. Six key issues likely to affect future ACO growth and development are discussed, and some potential "diagnostic" indicators for assessing the likelihood of potential antitrust violations are presented.

Keywords: ACO taxonomy; accountable care organizations; quality of care.

Figure 1. ACO Care Management Capabilities by Leadership Model

**significant at p < 0.05 Source: The Dartmouth Institute for Health Policy and Clinical Practice, Geisel School of Medicine at Dartmouth; and the Center for Healthcare Organizational and Innovation Research (CHOIR), UC Berkeley School of Public Health, 2014

Figure 2. ACO Participation in Physician Performance Management/Accountability, percent within cluster who participate

Source: Shortell SM, Wu FM, Lewis VA, Colla CH and Fisher E.S. “A Taxonomy of Accountable Care Organizations for Policy and Practice.” Health Services Research. online, September 16, 2014. DOI: 10.111/1475-6773.12234. Reprinted with permission

Figure 3. ACO Participation in Payment Reform Strategies, percent within cluster with ACO or ACO Provider Group level participation

Source: Shortell SM, Wu FM, Lewis VA, Colla CH and Fisher E.S. “A Taxonomy of Accountable Care Organizations for Policy and Practice.” Health Services Research, online, September 16, 2014. DOI: 10.111/1475-6773.12234. Reprinted with permission.

Figure 4

A. Mean Quality Scores for California Medical Groups, Including Kaiser Permanente B. Mean Quality Scores for California Medical Groups, Excluding Kaiser Permanente

Figure 4

A. Mean Quality Scores for California Medical Groups, Including Kaiser Permanente B. Mean Quality Scores for California Medical Groups, Excluding Kaiser Permanente

Figure 5. Outlook on the ACO Model

**significant at p < 0.05 Source: National Survey of Accountable Care Organizations. The Dartmouth Institute for Health Policy and Clinical Practice, and Center for Healthcare Organizational and Innovation Research (CHOIR), UC Berkeley School of Public Health.