Alphabetic Index
As we discussed in Lesson 2, the Alphabetic Index indents subterms and lists them alphabetically under the main term. Subterms further define the main term. In certain instances, terms are indented under subterms that define a condition in even greater detail.
On the right is an example from the Alphabetic Index. The main term, Glioblastoma, appears in alphabetical order within the Index. The Alphabetic Index includes indented subterms below the main term, shown by dashes (-).
Glioblastoma (multiforme)
- with sarcomatous component
- - specified site -see Neoplasm, malignant, by site
- - unspecified site C71.9
- giant cell
- - specified site —see Neoplasm, malignant, by site
- - unspecified site C71.9
- specified site —see Neoplasm, malignant, by site
- unspecified site C71.9
Note: Use 2023 ICD-10-CM codes for discharges and patient encounters occurring from discharges from October 1, 2022, through September 30, 2023.
Use 2024 ICD-10-CM codes for discharges and patient encounters occurring from discharges from October 1, 2023, through September 30, 2024.