The Relationship Between Governing Board Composition and Medicare Shared Savings Program Accountable Care Organizations Outcomes: an Observational Study

Background: Early studies of Medicare Shared Savings Program (MSSP) accountable care organizations (ACOs) suggested that physician leadership was an important driver of ACO success, but it is unknown whether the demographic and professional composition of current MSSP ACO governing boards is associated with ACOs\u27 publicly reported outcomes. Objective: To investigate whether governing boards with higher physician participation and greater female involvement have better outcomes. Design: Cross-sectional observational study. Participants: All 2017 MSSP ACOs identified by the Center for Medicare and Medicaid Services ACO Public Use Files (PUF). Main measures: We collected governing board composition from ACO websites in 2019. Outcome metrics included risk-standardized readmission and unplanned admissions rates. We used descriptive statistics and linear regression models to examine the association between board composition and outcomes. Key results: Of the 339 ACOs that still existed in 2019 and had available data, 77% had physician-majority boards and 11.5% had no women on their boards. Eighty-nine percent reported a Medicare beneficiary on their board, of which about one-third had a woman representative. The average number of members on MSSP ACO boards was 12, with a mean of 67% physicians and 24% women. Board composition varied minimally by ACO characteristics, such as geographic region, number of beneficiaries, or type of participants. Higher levels of physician participation in ACO governing boards were associated with lower all-cause unplanned admission rates for patients with heart failure (p = - 0.26, p \u3c 0.001) and for patients with multiple chronic conditions (p = - 0.28, p = 0.001). The number of women on the board was not associated with any outcome differences. Conclusions: MSSP ACO governing boards were predominately male and physician-led. Physician involvement may be important for achieving quality goals, while lack of female involvement showcases an opportunity to diversify boards. Keywords: ACOs; gender; governance; healthcare delivery