North Carolina has built a coordinated medical system for the poor that includes old-style house calls. And it's making a big difference.

The patient-centered medical home replaces episodic treatment based on individual illnesses with long-term coordinated care. It has several key components:

Personal physician: Patients have an ongoing relationship with a personal physician, who leads a team responsible for addressing all of their health needs and coordinating their care.

Coordinated care: Treatment is facilitated by health information technology and other means to assure that patients get the necessary medical attention in a culturally and linguistically appropriate manner.

Quality and safety: Evidence-based medicine guides decision making, and physicians participate in ongoing quality improvement and monitoring.

Enhanced access: Physician practices offer expanded hours, open scheduling and new forms of communication to ensure that primary-care physicians are available when needed.

Adapted from "Physican Practice Connections -- Patient-Centered Medical Home," a report from the National Committee for Quality Assurance, and from "Joint Principles of the Patient-Centered Medical Home," a March 2007 report from the American Academy of Pediatrics, the American Academy of Family Physicians, and the American College of Physicians.