Clinical Classifications Software (CCS), formerly known as Clinical Classifications for Health Policy Research (CCHPR), consists of 260 diagnosis categories. This system is based on ICD-9-CM codes. All diagnosis codes are classified. All E-codes (External Causes of Injury and Poisoning) are combined into the last category, 260.

DCCHPRn is coded as follows:

• DCCHPRn ranges from 1 to 260 if the diagnosis code (DXn) is valid by the HCUP criteria, which allows a six-month window (three months before and three months after) around the official ICD-9-CM coding changes (usually October 1), for anticipation of or lags in response to official ICD-9-CM coding changes.
• DCCHPRn is missing (.), if there is no diagnosis code (DXn = " ").
• DCCHPRn is set to invalid (.A), if the diagnosis code (DXn) is invalid (DXVn = 1).

DCCHPRn is retained (values 1-260) when a valid diagnosis is flagged as inconsistent with age or sex (DXVn = .C). For best results, use DCCHPRn only when the diagnosis is valid and consistent (DXVn = 0).

Beginning in the 1998 data, this data element is called DXCCSn.

Labels

Labels for CCS, formerly known as CCHPR, categories are provided as an ASCII file in HCUP Tools: Labels and Formats.

Formats

Formats to label CCS, formerly known as CCHPR, categories are documented in HCUP Tools: Labels and Formats. Both sixteen-and forty-character labels are available.

A format is also available to map CCS codes into a few broad classes of conditions based on ICD-9-CM chapters. These formats are also documented in HCUP Tools: Labels and Formats.