Final answer:
The biggest barrier to the Accountable Care Organization (ACO) model is difficulty in coordinating care, exacerbated by work overload, physical demands, patient concerns, and interactions with medical staff, particularly physicians.
Step-by-step explanation:
The question asks about the biggest barrier to the Accountable Care Organization (ACO) model. It's important to understand that ACOs are groups of doctors, hospitals, and other health care providers, who come together voluntarily to give coordinated high-quality care to their Medicare patients. One of the major barriers is Difficulty in coordinating care. This is due to a combination of factors including work overload, the physical demands of the job, varying patient concerns, and often complex interactions with other medical staff, predominantly with physicians. The necessity for coordinated care is a pillar of the ACO model, which aims to ensure that patients get the right care at the right time, while avoiding unnecessary duplication of services and preventing medical errors.