When a medical record contains more than one diagnosis, choosing the correct ICD-10-CM codes is only part of the job. You also need to know which diagnosis should be listed first and which codes should follow. This is where ICD-10-CM sequencing becomes important. For beginners, sequencing can feel confusing because there is no single rule that applies to every case. Sometimes the Tabular List gives you a clear instruction such as Code First or Use Additional Code. In other cases, you need to consider the reason for the encounter, chapter-specific guidelines, and the relationship between the documented conditions. The good news is that sequencing becomes much easier once you stop…

If you are learning medical coding, understanding Code First vs Use Additional Code vs Code Also in ICD-10-CM can be confusing at first. All three instructions may tell you that more than one diagnosis code is needed, but they do not all mean the same thing. The biggest difference is sequencing. Sometimes ICD-10-CM clearly tells you which condition should be coded first. In other situations, two codes may be needed, but the order depends on the circumstances of the encounter. Once you understand that basic idea, these instructional notes become much easier to recognize and apply. In this guide, we will break down Code First, Use Additional Code, and Code…