In ICD-10-CM, three character codes are reported only when there are no further what?

In ICD-10-CM, three-character codes represent the highest level of classification without any further subdivisions or specificity. When a three-character code is utilized, it indicates that the condition or diagnosis has been fully captured within that code, and there are no additional details (such as location, cause, or severity) that would require further breakdown into four or five-character codes.

For instance, a three-character code may classify a certain disease broadly, but if a more precise description is available, it would be represented by a longer code that provides additional detail. Hence, the correct identification of the need for subdivisions illustrates the coding structure's intent to ensure accuracy and specificity in medical documentation and billing. This fosters a clearer understanding of diagnoses and treatments in medical records.