Health Maintenance Organization
In the United States a health maintenance organization (HMO) is a medical insurance group that provides health services for a fixed annual fee. It is an organization that provides or arranges managed care for health insurance, self-funded health care benefit plans, individuals, and other entities in the United States, acting as a liaison with health care providers (hospitals, doctors, etc.) on a prepaid basis. The Health Maintenance Organization Act of 1973 required employers with 25 or more employees to offer federally certified HMO options if the employer offers traditional healthcare options. Unlike traditional indemnity insurance, an HMO covers care rendered by those doctors and other professionals who have agreed by contract to treat patients in accordance with the HMO's guidelines and restrictions in exchange for a steady stream of customers. HMOs cover emergency care regardless of the health care provider's contracted status.
HMOs often require members to select a primary care physician (PCP), a doctor who acts as a "gatekeeper" to direct access to medical services but this is not always the case. PCPs are usually internists, pediatricians, family doctors, geriatricians, or general practitioners (GPs). Except in medical emergency situations, patients need a referral from the PCP in order to see a specialist or other doctor, and the gatekeeper cannot authorize that referral unless the HMO guidelines deem it necessary. Some HMOs pay gatekeeper PCPs set fees for each defined medical procedure they provide to insured patients (fee-for-service) and then capitate specialists (that is, pay a set fee for each insured person's care, irrespective of which medical procedures the specialists performs to achieve that care), while others use the reverse arrangement.
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