System for the advance financing of medical expenses through contributions or taxes paid into a common fund to pay for all or part of health services specified in an insurance policy or law.
The key elements are advance payment of premiums or taxes, pooling of funds, and eligibility for benefits on the basis of contributions or employment without an income or assets test. Health insurance may apply to a limited or comprehensive range of medical services and may provide for full or partial payment of the costs of specific services. Benefits may consist of the right to certain medical services or reimbursement of the insured for specified medical costs. Private health insurance is organized and administered by an insurance company or other private agency; public health insurance is run by the government (see social insurance ). Both forms of health insurance are to be distinguished from socialized medicine and government medical-care programs, in which doctors are employed directly or indirectly by the goverment, which also owns the health-care facilities (e.g., Britain's National Health Service ). See also insurance .