The Medicare program does not cover all services. For many commonly ordered tests (e.g. cholesterol, glucose, Prothrombin Time), Medicare will reimburse only when specific criteria are met. The Centers for Medicare & Medicaid Services (CMS) have developed National Coverage Determinations that govern which diagnoses are considered "reasonable and necessary" according to Medicare rules for reimbursement.
Local Coverage Determinations (LCD) have also been developed for a limited number of tests (i.e. Flow Cytometry, Reticulocyte Count) in a regional coverage area. The NCD or LCD includes covered diagnoses for each test.
However, there are instances where a particular treatment protocol may make monitoring a certain laboratory test. (e.g. a medication a patient is taking may affect thyroid function so the practitioner monitors the TSH on the patient). If the patient's sign/symptoms/diagnosis are not among the diagnoses listed in the appropriate NCD, an ABN must be completed.
The practitioner should discuss the possibility of claim denial with the patient and the reason(s) the test should be performed so s/he is able to make an informed decision whether or not to proceed with the service.
The ABN consists of four required components: Patient Demographic information (Name, Medical Record Number, Date of Service, Medicare HINC#), The test(s) subject to the ABN, the patient's desire to have the test performed (YES, it should be performed and the patient will pay for it or NO do not perform the test), The patient's signature and date.
ABNs should be completed for Medicare beneficiaries ONLY