The Council of Accountable Physician Practices (CAPP) engaged the Institute for Accountable Care (IAC) to review recent literature to assess the current state of research on the characteristics and performance of accountable care organizations (ACOs) and accountable physician groups. CAPP has promoted five elements as essential to accountable care:

1. Coordinated care
2. Outcomes-based payment
3. Health information technology
4. Physician leadership
5. Quality improvement

This review focuses primarily on the first two elements.

Much of the recent literature on accountable care has focused on ACOs. This review defines accountable care more broadly than ACOs and considers the performance of organized physician groups, integrated health systems and Medicare Advantage programs. This review focuses on studies of programs that aim to improve outcomes for populations and with payment models tied to a global budget target, and the authors supplement some findings from the literature with their own observations based on publicly available data on Medicare accountable care programs.

It is the hope of CAPP that this review will help future researchers focus on gaps and opportunities for additional research that might help make the case of accountability and payment reform in health care.