With FY 2027 ICD-10-CM changes now in effect, healthcare organizations are balancing coding updates, productivity expectations, and ongoing concerns about claim accuracy. But not every coding issue involves a new or revised diagnosis code.
Sometimes, the correct code is selected, but an overlooked instructional note leads to incorrect sequencing or incomplete diagnosis reporting.
For experienced coders, familiar diagnoses can make code selection feel routine. However, the Alphabetic Index is only the starting point. The Tabular List tells us how the code must actually be reported.
Code First: Sequencing matters.
A Code first instruction indicates that an underlying condition must be sequenced before the code containing the instruction when applicable.
These notes commonly appear with manifestation codes that describe conditions resulting from an underlying disease.
Selecting both diagnoses does not automatically mean they have been reported correctly. Sequencing must follow the applicable instructions.
Use Additional Code: One code may not tell the whole story.
A Use additional code instruction indicates that a secondary code should be assigned, when applicable, to provide a more complete description of the condition.
These instructions may identify manifestations, associated conditions, or additional clinical details.
The additional code follows the code containing the instruction, consistent with applicable sequencing requirements.
Code Also: Additional reporting without automatic sequencing.
A Code also instruction indicates that two codes may be required to fully describe a condition.
Unlike Code first and Use additional code, this instruction does not independently establish sequencing order.
Sequencing depends on the circumstances of the encounter and any other applicable instructions.
Other conventions deserve attention.
An Excludes1 note generally indicates that the excluded condition should not be reported with the code above the note, although an exception may apply when the conditions are unrelated.
An Excludes2 note indicates that the excluded condition is not included in the code, but both conditions may be reported when appropriate.
Includes notes, combination-code instructions, and other conventions also deserve review.
Back to basics means checking the instructions.
Even when a diagnosis seems familiar, reviewing the Tabular List helps confirm code selection, sequencing, and additional reporting requirements.
For organizations, recurring errors involving these fundamentals may indicate opportunities for focused education or internal review.
BCA, Inc. helps healthcare organizations address these concerns through auditing, targeted education, and consulting. By identifying coding inconsistencies, clarifying instructional requirements, and reinforcing consistent practices, BCA can help teams strengthen accurate, defendable diagnosis reporting.
Sometimes, improving coding accuracy starts with a simple habit: don’t stop at the Alphabetic Index.
Book your consultation today with one of our experts.