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".
On the Headed Web SDK, a section can include icdCode and hccCode on the Diagnosis type. Those fields are not the same as auto-generating ICD-10 for new problems during the visit. Pass existing diagnoses into the Web SDK session, and retrieve suggested codes from Ambient API structured data when you need them.
You can use HCC output from Ambient API structured data to support risk-adjustment workflows or value-based care reporting.

	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.