Specialist Engagement in Population-Based Payment Models

Specialist Engagement in Population-Based Payment Models


While specialized care drives the vast majority of health care spending in the United States and two-thirds of physicians are specialists, specialty physicians have not been sufficiently engaged in population-based payment models, such as accountable care organizations (ACOs), to date. Poor specialty engagement limits the potential impact these payment reforms can have given their breadth and reach. Reasons for this limited engagement include organizational barriers (e.g., lack of infrastructure or pathways to support provider communications), care delivery challenges (e.g., poor coordination between specialists and primary care providers) and policy-related barriers (e.g., restrictions on the distribution of shared savings). Overall, these challenges lead to misaligned incentives between specialists and ACOs.

While specialist engagement in ACOs has been challenging to date, our preliminary work suggests ACOs are attempting to overcome these challenges through various strategies. There is a need for evidence about which of these strategies are most effective for which types of ACOs under which circumstances, as well as what policies and payment model design factors affect their implementation and effectiveness.

Project Overview

This project aims to explore how to enhance specialist engagement in population-based payment models. The project team will develop a report synthesizing the evidence regarding the involvement and impact of specialists in ACOs, the organizational and policy-related barriers to specialist engagement, promising strategies for specialist engagement, and relevant population-based payment model policies that affect specialist engagement. The project team will also convene and interview a variety of key stakeholders to better understand real-world experiences and develop solutions for enhancing specialist engagement. Drawing on the information generated during these activities, the project team will draft and disseminate a broad range of recommendations for payers and ACOs to enhance specialist engagement in population-based payment models.


This project is supported by a grant from Arnold Ventures.

Research Team

Jonathan Gonzalez-Smith

Jonathan Gonzalez-Smith, MPAff

Associate Research Director

Katie Huber

Katie Huber, MPH

Senior Policy Analyst

Margolis Summer Experience

Samantha Murrell

2022 Margolis Intern

Robert Saunders

Robert Saunders, PhD

Senior Research Director, Health Care Transformation
Adjunct Associate Professor
Senior Team Member
Margolis Core Faculty


Sherrie Wang

Policy Research Assistant