When selecting an ICD-10-CM diagnosis code, what is the first step?

The first step in selecting an ICD-10-CM diagnosis code is to search for the main term in the Alphabetic Index. This is crucial because the Alphabetic Index serves as a guide to locate the appropriate codes based on the condition being documented. By identifying the main term, coders can effectively navigate to the relevant section in the codebook, which will lead them to the related diagnosis codes. This structured approach helps ensure that the code chosen reflects the patient's condition accurately and aligns with the coding guidelines.

Once the main term is identified in the Alphabetic Index, it can then be cross-referenced with the Tabular List, where additional information such as inclusion and exclusion notes, as well as code specifics, can be considered to ensure coding accuracy. Therefore, starting with the main term in the Alphabetic Index is foundational and establishes a systematic method for coding that is essential for accurate medical billing and documentation.