Diagnosis codes

What Is the Difference Between ICD-10 and HCC Codes?

ICD-10 and HCC codes serve different purposes in clinical documentation:ICD-10 (International Classification of Diseases, 10th Revision)

A standardized system of codes used to classify and record diagnoses, symptoms, and procedures.
Used for billing, clinical documentation, and interoperability across healthcare systems.
Example: I10 = Essential hypertension.
ICD-10 is the primary identifier Suki uses internally to match, deduplicate, and process diagnoses.

HCC (Hierarchical Condition Category)

A risk-adjustment coding model used primarily in value-based care and Medicare Advantage programs.
HCC codes are derived from ICD-10 codes: CMS groups related ICD-10 codes into HCC categories to estimate a patient’s expected healthcare costs.
Not every ICD-10 code maps to an HCC category: only those that significantly affect patient risk scores do.
Example: ICD-10 I10 (Essential hypertension) maps to HCC 136.

How they relate in Suki structured data:

Suki processes and stores diagnoses using ICD-10 as the source of truth.
In API structured data, HCC categories appear in the diagnosis codes array with type: "HCC".
In the Web SDK, the hccCode field in the Diagnosis type surfaces the HCC category that corresponds to the ICD-10 code, when one exists.
You can use HCC output to support risk-adjustment workflows or value-based care reporting in your integration.

	ICD-10	HCC
Purpose	Clinical diagnosis coding	Risk adjustment and cost prediction
Scope	All diagnoses	Subset of high-impact diagnoses
Used by	All payers, EHRs	Medicare Advantage, value-based care
In Suki	Primary identifier	Supplemental output field

See Ambient session structured data and Supported Diagnosis Codes for endpoint details.

Can I Send HCC Codes in Session Context?

No. Do not send HCC in session context. HCC is structured-data output only ("type": "HCC"). Send ICD10 or IMO in session context. If an HCC mapping exists for a problem, Suki includes it when you retrieve structured data.See Ambient session structured data.