I.A
Conventions for the ICD-10-CM
The conventions for the ICD-10-CM are the general rules for use of the classification independent of the guidelines. These conventions are incorporated within the Alphabetic Index and Tabular List of the ICD-10-CM as instructional notes.
In this section
- I.A.1The Alphabetic Index and Tabular List
- I.A.2Format and Structure:
- I.A.3Use of codes for reporting purposes
- I.A.4Placeholder character
- I.A.6Abbreviations
- I.A.7Punctuation
- I.A.8Use of “and”.
- I.A.9Other and Unspecified codes a. “Other” codes
- I.A.10Includes Notes
- I.A.11Inclusion terms
- I.A.12Excludes Notes
- I.A.13Etiology/manifestation convention (“code first”, “use additional code” and “in diseases classified elsewhere” notes)
- I.A.18Default codes
- I.A.19Code assignment and Clinical Criteria
ICD-10-CM Official Guidelines for Coding and Reporting, FY 2026 (effective October 1, 2025). Published by CMS and NCHS. Reproduced for reference — always verify against the official CMS release.