The organization of medical care is changing more rapidly now than at any point in the last century. For decades, health care was a cottage industry: physicians practiced independently or in small groups and had arms-length relationships with hospitals, imaging and laboratory facilities, and other health care entities. Those organizations alternately competed and cooperated as part of an informal local health care system.
Recent years have seen the advent of large, integrated, corporate medicine. Today, the typical US city has 3 to 4 integrated health care systems, generally anchored around large hospitals and extending to suburban areas.1 These systems are conglomerations of hospitals, primary care and specialist physicians, outpatient facilities, and postacute care facilities. There remains a fringe of unaffiliated institutions and physicians, but the number of such institutions is declining.
Cutler DM. Who Benefits From Health System Change?. JAMA. 2014;312(16):1639-1641. doi:10.1001/jama.2014.13491