health maintenance organization (HMO)

Public or private organization providing comprehensive medical care to subscribers on the basis of a prepaid contract. HMOs deliver a broad range of health services for a fixed fee. In the prepaid group-practice model, physicians are organized into a group practice with one insuring agency. A medical care foundation, or individual practice association, usually involves multiple insurance companies and reimburses members of a loose network of individual physicians from subscribers' prepaid fees. Originally viewed as a way to control health-care costs and meet increased demand for health services, HMOs have become controversial because some limit care by refusing to pay for tests or treatment against their own doctors' advice.