Inventory of Health Care Information Standards. National Center for Health Statistics (NCHS)


International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM)


International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM)

International Classification of Diseases Procedure Coding System (ICD-10-PCS)

Name of Standard: (1) International Classification of Diseases (ICD); Ninth Revision, Clinical Modification (ICD-9-CM) currently in use for morbidity reporting.

Contact For More Information

Marjorie S. Greenberg (MSG1@NCH11A.EM.CDC.GOV, 301-436-4253 Ext. 107, Fax 301-436-4233) or Donna Pickett (DFP4@NCH11A.EM.CDC.GOV, 301-436-7050 Ext.142, Fax 301-436 4233)

Description of Standard

The ICD-9-CM is the latest version of a classification that originated as the International List of Causes of Deaths, adopted in 1893 by the International Statistical Institute. The classification was revised at ten-yearly intervals and at the Sixth Revision Conference in 1948, the first undertaken by the WHO, its scope was extended to include non-fatal conditions and its use was recommended for morbidity statistics as well as for mortality. Subsequent revisions have enhanced its usefulness for morbidity applications by increasing the specificity of rubrics and by emphasizing manifestations of disease. Effective January 1979, the ICD-9-CM became the sole classification system used for morbidity reporting in the United States.

The ICD-9-CM, widely accepted and used in the health care industry, has been adopted by the federal government and the private sector for a number of purposes: data collection, quality of care analyses, resource utilization, research and reimbursement, and statistical reporting.

ICD-10-CM is currently under development, with a planned implementation date of October 1, 2000.

Readiness of Standard:

There are official coding guidelines used to instruct users on the classification. The ICD-9-CM classification and the guidelines are in the public domain and are available on CDROM from the Government Printing Office.

Is it implementable? (If so, is it fully or partially implementable?, explain)

The guidelines and classification are both in current use.

How can the standard be obtained?

The ICD-9-CM classification and the official national coding guidelines are in the public domain and are widely available. Both can be obtained through the Government Printing Office or through various publishers.

Does it require a separate implementation guide? (If so is the guide approved by the SDO?

Not applicable

Is there only one implementation guideline (or are there major options that impact compatibility)?

Not applicable

Is a conformance standard specified?

Not applicable

Are conformance test tools available?

Not applicable

Source of test tools?

Not applicable

If the standard is under development, what parts of it are ready now?

Work on the clinical modification (CM) of the International Classification of Diseases and Related Health Problems (ICD-10) is currently underway; it will undergo review in the Department of Health and Human Services in 1997. The final version is scheduled to be available by October 1, 1998.

What extensions are now under development?

What are the major milestones toward standards completion?

What are the projected dates for final balloting and/or implementation?

The planned implementation of ICD-10-CM, in conjunction with the Health Care Financing Administration's Procedure Coding System (ICD-10-PCS), is tentatively scheduled for October 1, 2000.

Please note any other indicators of readiness that may be appropriate.

Indicator of Market Acceptance

Both the classification and guidelines for it are in wide use with thousands of copies being used nationally for the submission of health insurance claims and for statistical data collection, performance measures, research, etc.

If the standard is an implementable standard, how many vendors, healthcare organizations and/or government agencies are using it?


Is this standard being used in other countries (which are they)?

The ICD-9 is used internationally for cause of death tabulation. The ICD-9-CM, the morbidity version of the ICD-9, is used in the United States primarily, but Australia and Israel use the ICD-9-CM for morbidity. These countries will be implementing the ICD-10 for both morbidity and mortality prior to the United States.

Please note any other relevant indicator of market acceptance within the public or private sector.

Many private vendors produce a variety of software and book products based on the ICD-9-CM.

Level of Specificity

If your standard is a guideline, how detailed is it?A.

The guidelines for the ICD-9-CM are broad guidelines for coding. They are not teaching manuals.

If it is an implementable standard, describe how detailed its framework is and its level of granularity.


Does the standard(s) reference or assume other standards to achieve more specificity?


If it includes or assumes code sets, which ones are they?

The ICD-9-CM is code set.

What is the description of the code set?

A medical statistical classification

How is the code set acquired?

The ICD-9-CM classification and the official national coding guidelines are in the public domain and are widely available. Both can be obtained through the Government Printing Office or through various publishers.

Is there a users' guide or some other assistance available on the code set?

WHO published an official rule book for mortality rules. The U.S. publishes official guidelines for the use of the ICD-9-CM for morbidity applications.

If the code set is currently in use, what is the extent of its use (e.g., approximate number of users)?

All health care claims must list the ICD-9-CM diagnosis code.

If the code set is under development, what are the projected dates of completion and implementation?


Relationships with other standards

Volume 3 of ICD-9-CM is the classification of procedures used in the inpatient setting. CPT is used by physicians and hospital-based outpatient departments for the coding of procedures. The Health Care Financing Administration is developing ICD-10-PCS to replace Volume 3.

Identify specific standards reconciliation or coordination activities.

NCHS serves as the North American Collaborating Center for the Classification of Diseases (ICD) and for the International Classification of Impairments, Disabilities, and Handicaps (ICIDH). NCHS is responsible for the coordination of all official disease classification activities in the United States relating to the ICD and its use, interpretation and periodic revision. [See also III (A)].

The ICD-9-CM Coordination and Maintenance Committee is the process by which the classification (Volumes 1, 2, and 3) is maintained and updated each year. The Coordination and Maintenance process ensures stability of the classification system and it s comparability with its parent system, ICD-9. Established in 1985, this Committee was formed to provide a public forum to discuss possible updates and revisions to the ICD-9-CM.

What portion of the specification and functionality is affected by this coordination? N/A

What conditions are assumed in order for this coordination to be effective?

All requests for modification are handled through the ICD-9-CM Coordination and Maintenance Committee. The Committee discusses such topics as the need to update the ICD-9-CM due to changes in medical technology, the need to provide greater specificity in classifying diagnoses (adding clinical detail and accuracy), and the need to correct inaccuracies in the classification. No official changes are made without being brought before this committee.

Although the Committee is a federal committee, suggestions for modifications come from both the public and private sectors, and interested parties are asked to submit recommendations for modification prior to a scheduled meeting.

Modifications are not considered without the expert advice of clinicians, epidemiologists, and nosologists (both public and private sectors).

Is this standard consistent with international standards? If so, which standards?

Yes. The ICD-9-CM is consistent with ICD-9, and ICD-10-CM similarly will be consistent with ICD-10.

What gaps remain among related standards that should be addressed?

Describe what is being done to address these gaps.

Identifiable Costs

Notes: ICD-10-CM

A. Please indicate the cost or your best estimate for the following:

- Cost of licensure

None, the classification is in the public domain

  • Cost of acquisition (if different from licensure)
  • Cost/timeframes for education and training/implementation

A two-year timeframe is planned to allow for training and system modifications and software development for the transition to ICD-10-CM.

- Please note any other cost considerations.