Medicare uses ICD-9 codes for diagnosing diseases and ensuring that patients receive an accurate diagnosis. The ICD-9 code is called the International Classification of Diseases, according to CMS.gov. It is part of a comprehensive coding system used by Medicare and Medicaid to govern the safety and care of patients.
The International Classification of Diseases is a medical code that is updated periodically to reflect evolution in the medical industry. ICD-9 is the official HIPAA code set for identifying conditions and is used uniformly by health care agencies, physicians, hospitals and health care workers. The ICD classification system contains several volumes, according to ACEP.org. Within its scope are instructions for procedure coding in several settings, including hospitals and in-patient facilities. ICD-9 regularly changes, and practitioners who use it for coding must comply with new standards within a set period. These instructions are in Volume Three of the ICD-9 code, while physicians use Volumes One and Two.
Initially, ICD-9 was instituted as a statistical disease-tracking tool during the late 1800s. It then evolved into a diagnostic tool and is used in the United States today for morbidity tracking. Diagnostic codes within this system contain a series of letters and numbers; the first three to five codes represent illnesses and ailments, while the following letters indicate poisoning, causes of injury and side effects.