How to Use an ICD-10 Encoder for Risk Adjustment

How to Use an ICD-10 Encoder for Risk Adjustment

An ICD-10-CM encoder is the most important tool in a risk adjustment coder's workflow. It lets you search for diagnosis codes, verify their specificity, check HCC mappings, and ensure you are coding to the highest level of detail supported by the documentation.

This guide walks you through how to use an encoder effectively for HCC coding — with examples from HCC Buddy's free encoder.

What Is an ICD-10 Encoder?

An ICD-10 encoder is a searchable database of all ~72,000 ICD-10-CM diagnosis codes. A good encoder provides:

Step 1: Search for the Condition

Start by typing the condition name or a partial ICD-10 code into the search bar.

Search tips:

The encoder returns a ranked list of matching codes. Results typically show the code, description, and whether it is billable.

Step 2: Check Billable Status

Only billable codes (also called valid codes or codes with maximum specificity) can be submitted on claims. Non-billable codes are category headers that require additional characters.

Example:

If you select a non-billable code, the encoder should show its child codes so you can drill down to the correct specificity level.

Step 3: Read the Instructional Notes

This is where coders make or break accuracy. Every code can have several types of notes:

Includes Notes

Lists conditions that are covered by this code. If the documentation uses any of these terms, this code applies.

Excludes 1 — Do NOT Code Together

These conditions cannot be coded with the current code. They are considered mutually exclusive.

Excludes 2 — May Coexist

These conditions are not included in the current code, but can be coded separately if documented. This is a common area of confusion — Excludes 2 does NOT mean "do not code."

Use Additional Code

Tells you to add a secondary code. For example, diabetes codes often instruct you to use an additional code for the specific complication.

Code First

The opposite of Use Additional — it tells you that another condition should be sequenced first.

Step 4: Verify the HCC Mapping

For risk adjustment coding, this is the critical step. After selecting the correct ICD-10-CM code, check:

1. Does it map to an HCC? — Not all codes do. The encoder should clearly indicate "HCC" or "Non-HCC."

2. Which HCC number? — The specific HCC category (e.g., HCC 37 for Diabetes with Chronic Complications).

3. Which model version? — V24 and V28 may have different mappings for the same code. Payment Year 2026 uses a blend.

4. What is the RAF weight? — Higher weights mean greater reimbursement impact.

Example in HCC Buddy:

Searching for E11.22 (Type 2 diabetes mellitus with diabetic chronic kidney disease) shows:

Step 5: Navigate the Code Hierarchy

Use the breadcrumb navigation to understand where a code sits in the ICD-10-CM structure:

Chapter 4 → E08-E13 → E11 → E11.2 → E11.22

This helps you:

Step 6: Check Child Codes

If you selected a category code, look at its children to find the most specific option:

E11.6 (Diabetes with other specified complications) has children:

Always code to the highest level of specificity supported by documentation.

Common Encoder Workflow for Risk Adjustment

1. Read the medical record — identify all documented conditions

2. Search the encoder for each condition

3. Verify the code is billable and at maximum specificity

4. Check HCC mapping — does it contribute to risk adjustment?

5. Review instructional notes — any additional codes required?

6. Confirm documentation support — does the record support this code per MEAT criteria?

7. Submit the code with confidence

Why HCC Buddy Is Built for Risk Adjustment Coders

Most general-purpose encoders bury HCC information or require a separate lookup. HCC Buddy puts HCC mapping front and center:

Start using the encoder at hccbuddy.com/encoder.