Medical codes are assigned to procedures and diagnoses to bill insurance companies for the services doctors and other health care workers provide to patients. Diagnosis codes must be correctly linked to procedures to establish medical necessity.
Diagnosis, or ICD-9, codes, are assigned for a confirmed diagnosis or presenting symptoms. Insurance companies use diagnosis codes to verify medically necessary services.
Current procedural terminology (CPT) codes are used to report procedures or examination services performed by health care professionals. Each CPT code must be linked to a diagnosis code to establish medical necessity.
Medical Code Linkage
Medical code linkage is when diagnosis codes are listed in corresponding order to CPT codes on an insurance claim form. Failure to properly link codes can result in claim denials. For example, a patient complains of shortness of breath, so the physician orders a one view chest X-ray. The patient also complains of headache. Line 1 of the diagnosis reporting section of the claim form would include 786.05 for shortness of breath. The code for a single view chest X-ray, 71010, would be listed as the primary procedure. The code for headache, 784.0, would be included as a secondary diagnosis.