What Is the Meaning of ICD-9?

Medical coding is systematic coding of diseases and injuries.

In the United States, a medical classification system is used to collect information regarding diseases and injuries. This system is the International Classification of Diseases (ICD). The ICD-9 means the Ninth Revision of the International Classification of Diseases. The National Center for Health Statistics and the Centers for Medicare and Medicaid Services, two departments in the United States Department of Health and Human Services, provide guidelines for medical coding and reporting using the ICD-9.

ICD-9 Volumes

Coders must train and take certification tests

There are three volumes of classifications. Volume One, the Tabular List of Diseases and Injuries; Volume Two, the Alphabetic Index of Diseases and Injuries; and Volume Three, the Tabular List and Alphabetic Index of Procedures, used for surgeries and inpatient procedures. Volumes One and Two are primarily used for outpatient facilities.

Classification System

Basic codes are used to classify an injury or a disease. The codes consist of three digits and are referred to as categories. The categories are expanded by the addition of two more numbers for subcategories. A decimal separates the basic three-digit code from the subcategory. For example, a diabetic's condition that is uncontrolled (Type 3) would be coded as 250.03: insulin-dependent diabetes mellitus (250), uncontrolled (03).

Coding

A coder first locates the primary condition in Volume Two, the Alphabetic Index of Diseases and Injuries. The coder then proceeds to look for sub-terms, which further describes the condition. Once the coder has located the code in Volume Two, the coder then must verify the code in Volume One, the Tabular List of Diseases and Injuries. The tabular list has 17 chapters, each with a range of codes. For example, neoplasms are from 140 through 239 and Mental Disorders consist of codes from 290 through 319.

Additional Codes

Coders must sometimes read medical records to obtain the correct diagnosis.

The coding process also includes V Codes (the main reason for the patient's visit), E Codes (the external causes of injuries or poisonings), and M Codes ( to identify the nature and behavior of neoplasm-cancer cells) to provide additional information related to the condition. In addition, braces, brackets and slanted squares are used to further assist the coder in choosing the appropriate code. There are also additional coding conventions and rules to assist the coder. For example, if the physician is unable to diagnose the patient, the coder may have to code the signs and symptoms. Coders must not code for a specific condition unless they have a confirmed diagnosis.

Considerations

The ICD-9 is extremely specific in terms of coding to prevent billing errors. Physicians, hospitals, nursing homes and other medical facilities depend on the correct coding. In addition, if a coder codes incorrectly, such as coding HIV as a diagnosis when the condition is suspect but not verified, the code can possibly have an impact on the patient's insurance coverage, their job or the life.

References

• ICD9CM Chrisendres: "The International Classification of Diseases, 9th Revision, Clinical Modification"
• Center for Disease Control and Prevention: Classification of Diseases, Functioning, and Disability
• Center for Medicare and Medicaid Services: ICD-9 Provider & Diagnostic Codes-Overview

Resources

• "ICD-9-CM Coding Handbook 2010"; Faye Brown; 2010