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CCS (Clinical Classifications Software) - Synopsis

Search CCS in the UMLS Metathesaurus
(requires a free UMLS license)

Web site

The Clinical Classifications Software (CCS) for ICD-9-CM was developed and is maintained by the Healthcare Cost and Utilization Project (HCUP), which is sponsored by the Agency for Healthcare Research and Quality (AHRQ).

CCS is used to analyze costs, usage, and outcomes associated with patient diagnoses and procedures.

CCS is composed of diagnoses and procedures categories, which are organized in two related classification systems. The single-level system consists of 285 mutually-exclusive diagnosis categories, 231 mutually-exclusive procedure categories, and no hierarchical structure. The multi-level system uses the single-level categories and International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) codes in a hierarchical system consisting of four levels for diagnoses and three levels for procedures.

CCS was formerly the Clinical Classifications for Health Policy Research (CCHPR).

CCS is used by health plans, policymakers, and researchers.

Update Frequency
CCS is updated annually.

Metathesaurus Update Frequency
CCS was last updated in the Metathesaurus in 2005.

Sites Consulted

  1. Clinical Classification Software (CCS) for ICD-9-CM Fact Sheet [Internet]. Rockville (MD): Agency for Healthcare Research and Quality; [modified 2009 Dec 16; cited 2010 Jan 25]. Available from: