One of the key purposes of ICD is interoperability. Without it, exchanging EMR/EHR data between hospitals would become inconsistent so difficulty in health information exchange occurs. Another one is clinical communication problem such as a diagnosis written in free text or using local codes may cause misinterpretation, especially when patients move between hospitals which could lead to errors in treatment, duplication of tests, and poor continuity of care. Many insurance systems use ICD codes for claims, reimbursement, and fraud detection. Without it, billing would be inconsistent and inefficient for both hospitals and insurance providers.
