Medicare demands an Advanced Beneficiary Notice (ABN). The ABN is designed to assist patients in making an informed decision about whether or not they want to get specific laboratory tests for which Medicare funding is likely to be rejected. Only when it finds that a service is fair and essential does the Medicare program pay for it. Only if the patient has specific medical problems, symptoms, or diseases is a test considered medically required by Medicare. These tests are known as Limited Coverage Tests by Medicare. The patient will be liable for the cost of the tests if Medicare rejects them if they decide to undergo the Limited Coverage tests.