Dimension table: ICD diagnoses

Hospital level table

The d_icd_diagnoses table

This table defines International Classification of Diseases (ICD) Version 9 and 10 codes for diagnoses. These codes are assigned at the end of the patient’s stay and are used by the hospital to bill for care provided.

  • diagnoses_icd ON icd_code

Table columns

Name Postgres data type
icd_code VARCHAR(10)
icd_version INTEGER
long_title VARCHAR(300)

Detailed Description

icd_code, icd_version

icd_code is the International Coding Definitions (ICD) code.

There are two versions for this coding system: version 9 (ICD-9) and version 10 (ICD-10). These can be differentiated using the icd_version column. In general, ICD-10 codes are more detailed, though code mappings (or “cross-walks”) exist which convert ICD-9 codes to ICD-10 codes.

Both ICD-9 and ICD-10 codes are often presented with a decimal. This decimal is not required for interpretation of an ICD code; i.e. the icd_code of ‘0010’ is equivalent to ‘001.0’.

ICD-9 and ICD-10 codes have distinct formats: ICD-9 codes are 5 character long strings which are entirely numeric (with the exception of codes prefixed with “E” or “V” which are used for external causes of injury or supplemental classification). Importantly, ICD-9 codes are retained as strings in the database as the leading 0s in codes are meaningful.

ICD-10 codes are 3-7 characters long and always prefixed by a letter followed by a set of numeric values.


The long_title provides the meaning of the ICD code. For example, the ICD-9 code 0010 has long_title “Cholera due to vibrio cholerae”.

Last modified August 14, 2020: update website to use docsy (adc506c)