ICD-10-CM/PCS consists of two parts:
- ICD-10-CM for diagnosis coding
- ICD-10-PCS for inpatient procedure coding
ICD-10-CM is for use in all U.S. health care settings. Diagnosis coding under ICD-10-CM uses 3 to 7 digits instead of the 3 to 5 digits previously used with ICD-9-CM, but the format of the code sets is similar.
ICD-10-PCS is for use in U.S. inpatient hospital settings only. ICD-10 PCS uses 7 alphanumeric digits instead of the 3 or 4 numeric digits used under ICD-9-CM procedure coding. Coding under ICD-10-PCS is much more specific and substantially different from ICD-9-CM procedure coding.
The transition to ICD-10 occurred because ICD-9 produced limited data about patients' medical conditions and hospital inpatient procedures. ICD-9 is 30 years old, has outdated terms, and is inconsistent with current medical practice. Also, the structure of ICD-9 limits the number of new codes that can be created, and many ICD-9 categories are full.
The files that are included on this page are provided by CMS as an introduction to ICD-10 coding and to answer frequently asked questions regarding the transition from ICD-9 to ICD-10. Additional information can be obtained from the
CMS website.