The Clinical Classifications Software Refined (CCSR) for International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM)-coded diagnoses classifies diagnoses into clinically meaningful categories, provides a means by which to identify specific clinical conditions using diagnosis codes, and can be used analytically to examine patterns in healthcare cost, utilization, and outcomes; perform rank utilization by diagnoses; and risk-adjust by clinical condition.

The CCSR balances the retention of the clinical concepts included in the CCS categories under ICD-9-CM and capitalizes on the specificity of ICD-10-CM diagnoses by creating new clinical categories. In addition, the CCSR allows ICD-10-CM diagnosis codes to be cross classified into more than one category because individual codes can be used to document multiple conditions or a condition and a common symptom/manifestation. The refinement process was informed by American Health Information Management Association-certified ICD-10-CM trainers and reviewed by a team of clinical experts. The team extensively reviewed the CCSR at each stage of its development using the HCUP State databases for quality control testing.

CCSR categories are organized by body system. Each body system is abbreviated using a three-character scheme such as NEO for Neoplasms and CIR for Diseases of the Circulatory System. Individual CCSR categories are numbered sequentially with the numbering scheme starting at "001" within each body system (i.e., there is a CCSR 001 for each body system).

Each data element DXCCSR_AAAnnn identifies whether the CCSR category was triggered by a diagnosis code on the record. The value of AAA indicates the body system. The value of nnn indicates the specific category within the body system. For example, the data element DXCCSR_CIR007 indicates CCSR category for Essential hypertension under the body system of Diseases of the Circulatory System. The value of the DXCCSR_AAAnnn data element indicates the following for the CCSR category identified by AAAnnn:

• The CCSR was not triggered by any ICD-10-CM diagnosis code on the input record (value 0).
• The CCSR was triggered by only the principal (or first-listed diagnosis) on the input record (value 1).
• The CCSR was triggered by both the principal (or first-listed diagnosis) and any secondary diagnosis on the input record (value 2).
• The CCSR was triggered by only secondary diagnosis code(s) on the input record (value 3).

Information on the CCSR (including a User Guide and listing of all CCSR categories) is available on the HCUP User Support website under Tools & Software.