ICD.9.CM - DIAGNOSTIC and SURGICAL PROCEDURE CODES

DEVELOPMENT OF THE INTERNATIONAL
CLASSIFICATION OF DISEASES

Diagnostic coding dates back to seventeenth-century England where statistical information was gathered through a system known as the London Bills of Mortality. By 1937 this method of tracking information had evolved into the International List of Causes of Death. The World Health Organization (WHO) published a statistical listing in 1948 that could be used to track both morbidity and mortality. This listing, the International Classification of Diseases (ICD), led the way for the current text in international use today - the International Classification of Diseases, 9th Revision (ICD.9).

By 1977, when the 9th revision was published, ICD.9 had attained wide international recognition. This prompted the United States National Center for Health Statistics to modify the statistical study with clinical information. These clinical modifications provided a way to classify morbidity data for indexing of medical records, medical case reviews, and ambulatory and other medical care programs, as well as for basic health statistics. The results was the International Classification of Diseases, 9th Revision, Clinical Modification (ICD.9.CM), commonly referred to as ICD.9. This version precisely delineates the clinical picture of each patient, providing exact information beyond that needed for statistical groupings and analysis of healthcare trends.

In 1988 Congress passed the Medicare Catastrophic Coverage Act, and ICD.9 coding took on new importance. Although this act was later repealed, the mandate requiring use of ICD.9 codes on each "Part-B" claim submitted by physicians was upheld. This mandate became effective on April 1, 1989. Basic guidelines regarding the use of ICD.9 codes were published by CMS(previously HCFA) and put into effect by each state. Failure to use, or correctly use, ICD.9 codes can lead to severe repercussions.

CMS(previously HCFA) GUIDELINES

CMS provided specific guidelines to aid in standardizing coding practices across the United States. These guidelines are summarized below:

• Identify each service, procedure, or supply with an ICD.9 code from 001.0 through V82.9 to describe the diagnosis, symptom, complaint, condition, or problem.
• Identify services or visits for circumstances other than disease or injury, such as follow-up care after chemotherapy, with V codes provided for this purpose.
• Code the primary diagnosis first, followed by the secondary, tertiary, and so on. Code any coexisting conditions that effect the treatment of the patient for that visit or procedure as supplement information. Do not code a diagnosis that is no longer applicable.
• Code to the highest degree of specificity. Carry the numerical code to the 4th or 5th digit when necessary. Remember, there are only approximately 100 valid three-digit codes; all other ICD.9 codes require additioanl digits.
• Code a chronic diagnosis as often as it is applicable to the patient's treatment.
• When only ancillary services are provided, list the appropriate V code first and the problem second. For example, if a patient is receiving only ancillary therapeutic services, such as physical therapy, use the V code first, followed by the code for the condition.
• For surgical procedures, code the diagnosis applicable to the procedure. If at the time the claim is filed the postoperative diagnosis is different than the preoperative diagnosis, use the postoperative diagnosis.

Extracted from: ICD.9.CM International Classification of Diseases, Ninth Revision
Available from: Medicode Publications, 5225 Wiley Post Way, Suite 500, Salt Lake City, Utah 84116-2889
Phone: 1-800-999-4600