A taxonomy of hospitals participating in Medicare accountable care organizations.

BACKGROUND: Medicare was an early innovator of accountable care organizations (ACOs), establishing the Medicare Shared Savings Program (MSSP) and Pioneer programs in 2012-2013. Existing research has documented that ACOs bring together an array of health providers with hospitals serving as important participants. PURPOSE: Hospitals vary markedly in their service structure and organizational capabilities, and thus, one would expect hospital ACO participants to vary in these regards. Our research identifies hospital subgroups that share certain capabilities and competencies. Such research, in conjunction with existing ACO research, provides deeper understanding of the structure and operation of these organizations. Given that Medicare was an initiator of the ACO concept, our findings provide a baseline to track the evolution of ACO hospitals over time. METHODOLOGY/APPROACH: Hierarchical clustering methods are used in separate analyses of MSSP and Pioneer ACO hospitals. Hospitals participating in ACOs with 2012-2013 start dates are identified through multiple sources. Study data come from the Centers for Medicare and Medicaid Services, American Hospital Association, and Health Information and Management Systems Society. RESULTS: Five-cluster solutions were developed separately for the MSSP and Pioneer hospital samples. Both the MSSP and Pioneer taxonomies had several clusters with high levels of health information technology capabilities. Also distinct clusters with strong physician linkages were present. We examined Pioneer ACO hospitals that subsequently left the program and found that they commonly had low levels of ambulatory care services or health information technology. CONCLUSION: Distinct subgroups of hospitals exist in both the MSSP and Pioneer programs, suggesting that individual hospitals serve different roles within an ACO. Health information technology and physician linkages appear to be particularly important features in ACO hospitals. PRACTICE IMPLICATIONS: ACOs need to consider not only geographic and service mix when selecting hospital participants but also their vertical integration features and management competencies.

Organizational Attributes Associated With Medicare ACO Quality Performance.

PURPOSE: To evaluate associations between geographic, structural, and service-provision attributes of Accountable Care Organizations (ACOs) participating in the Medicare Shared Savings Program (MSSP) and the ACOs' quality performance. METHODOLOGY: We conducted cross-sectional and longitudinal analyses of ACO quality performance using data from the Centers for Medicare and Medicaid Services and additional sources. The sample included 322 and 385 MSSP ACOs that had successfully reported quality measures in 2014 and 2015, respectively. RESULTS: Results show that after adjusting for other organizational factors, rural ACOs' average quality score was comparable to that of ACOs serving other geographic categories. ACOs with hospital-system sponsorship, larger beneficiary panels, and higher posthospitalization follow-up rates achieved better quality performance. CONCLUSION: There is no significant difference in average quality performance between rural ACOs and other ACOs after adjusting for structural and service-provision factors. MSSP ACO quality performance is positively associated with hospital-system sponsorship, beneficiary panel size, and posthospitalization follow-up rate.

Admission diagnoses among patients with heart failure: Variation by ACO performance on a measure of risk-standardized acute admission rates.

BACKGROUND: A key quality metric for Accountable Care Organizations (ACOs) is the rate of hospitalization among patients with heart failure (HF). Among this patient population, non-HF-related hospitalizations account for a substantial proportion of admissions. Understanding the types of admissions and the distribution of admission types across ACOs of varying performance may provide important insights for lowering admission rates. METHODS: We examined admission diagnoses among 220 Medicare Shared Savings Program ACOs in 2013. ACOs were stratified into quartiles by their performance on a measure of unplanned risk-standardized acute admission rates (RSAARs) among patients with HF. Using a previously validated algorithm, we categorized admissions by principal discharge diagnosis into: HF, cardiovascular/non-HF, and noncardiovascular. We compared the mean admission rates by admission type as well as the proportion of admission types across RSAAR quartiles (Q1-Q4). RESULTS: Among 220 ACOs caring for 227,356 patients with HF, the median (IQR) RSAARs per 100 person-years ranged from 64.5 (61.7-67.7) in Q1 (best performers) to 94.0 (90.1-99.9) in Q4 (worst performers). The mean admission rates by admission types for ACOs in Q1 compared with Q4 were as follows: HF admissions: 9.8 (2.2) vs 14.6 (2.8) per 100 person years (P < .0001); cardiovascular/non-HF admissions: 11.1 (1.6) vs 15.9 (2.6) per 100 person-years (P < .0001); and noncardiovascular admissions: 42.7 (5.4) vs 69.6 (11.3) per 100 person-years (P < .0001). The proportion of admission due to HF, cardiovascular/non-HF, and noncardiovascular conditions was 15.4%, 17.5%, and 67.1% in Q1 compared with 14.6%, 15.9%, and 69.4% in Q4 (P < .007). CONCLUSIONS: Although ACOs with the best performance on a measure of all-cause admission rates among people with HF tended to have fewer admissions for HF, cardiovascular/non-HF, and noncardiovascular conditions compared with ACOs with the worst performance (highest admission rates), the largest difference in admission rates were for noncardiovascular admission types. Across all ACOs, two-thirds of admissions of patients with HF were for noncardiovascular causes. These findings suggest that comprehensive approaches are needed to reduce the diverse admission types for which HF patients are at risk.

A taxonomy of accountable care organizations for policy and practice.

OBJECTIVE: To develop an exploratory taxonomy of Accountable Care Organizations (ACOs) to describe and understand early ACO development and to provide a basis for technical assistance and future evaluation of performance. DATA SOURCES/STUDY SETTING: Data from the National Survey of Accountable Care Organizations, fielded between October 2012 and May 2013, of 173 Medicare, Medicaid, and commercial payer ACOs. STUDY DESIGN: Drawing on resource dependence and institutional theory, we develop measures of eight attributes of ACOs such as size, scope of services offered, and the use of performance accountability mechanisms. Data are analyzed using a two-step cluster analysis approach that accounts for both continuous and categorical data. PRINCIPAL FINDINGS: We identified a reliable and internally valid three-cluster solution: larger, integrated systems that offer a broad scope of services and frequently include one or more postacute facilities; smaller, physician-led practices, centered in primary care, and that possess a relatively high degree of physician performance management; and moderately sized, joint hospital-physician and coalition-led groups that offer a moderately broad scope of services with some involvement of postacute facilities. CONCLUSIONS: ACOs can be characterized into three distinct clusters. The taxonomy provides a framework for assessing performance, for targeting technical assistance, and for diagnosing potential antitrust violations.