The evolving role of subspecialties in population health management and new healthcare delivery models.

New healthcare delivery models, including accountable care organizations (ACOs) and patient-centered medical homes, emphasize a more robust role for primary care. However, it is less clear how the roles and responsibilities of subspecialists should change as we enter a new paradigm of alternative payment models. Health systems seeking to better manage population health and control costs will need a clearer understanding of how best to incorporate subspecialty practitioners: What is a subspecialist's role? How does it vary by subspecialty? How should they be compensated? We argue that subspecialist compensation in ACOs and other new care delivery models should recognize the range of ways in which specialists can provide value to patients across a population-which varies depending on the provider's role in a patient's care. Only by more thoughtfully engaging, equipping, and compensating subspecialty practitioners can we achieve reform's central goal of better population health at a lower cost.