Risk Adjustment Overview

Risk Adjustment Factor (RAF) Gaps (also called "risk gaps") help identify potentially missing or incomplete risk-adjustment diagnoses for a Medicare Advantage patient in the current calendar year. The goal is to surface opportunities for providers and care teams to confirm/document conditions and ensure appropriate coding and billing.

A risk gap is calculated per patient and calendar year, for each relevant HCC (CMS-HCC v28). Zus continuously evaluates each patient's aggregated record - encounter diagnoses, clinical documents, medications, claims, and payer-provided gap files - and combines everything into a single, consistent gap per HCC.

Gap types

Every gap is one of three types, determined by when the condition was documented:

Gap type	Definition
Net-new	The condition is documented for the first time in the current measurement year.
Recapture	The condition was documented in a prior year but not yet this year.
Suspect	The condition hasn't been documented this year or within the recapture window, but evidence suggests it exists.

Recaptures and net-new gaps are calculated automatically as new data arrives. You can configure whether these determinations use exclusively claims data or include encounter diagnoses found in clinical data. You can also configure how many years back the recapture logic will look.

Suspects are identified two ways:

Basic suspecting runs automatically. It identifies encounter diagnoses recorded before the recapture window but within a configured lookback window (default 5 years).
Advanced suspecting can be run on an ad-hoc population or automatically ahead of upcoming appointments. It reviews the full text of all clinical documents (eg. CCDAs and PDFs) along with medication data to identify suspect conditions.

Every suspect carries a 1-5 confidence level, displayed as Low (1-3), Medium (4), or High (5). A historical encounter diagnosis is always High confidence (5). Advanced suspects are scored by evidence strength: explicit documentation scores higher than inference from medications or isolated findings.

Gap evidence

Every risk gap includes the evidence behind it, in two categories:

Supporting evidence directly supports the gap: encounter diagnoses, claims, payer records, and quoted passages from clinical documents.
Related resources provide context without being proof on their own: lab results, vitals, and screenings relevant to the condition.

Confidence follows the strongest supporting evidence. If a historical encounter diagnosis exists, the gap is High confidence regardless of what other evidence was found.

Gap status

Risk gaps carry a status indicating whether the gap is open or closed.

Status	Definition
`open-gap`	No evidence of the HCC being documented in the current year; the gap remains open.
`closed-gap`	The HCC is considered closed for the year (e.g., acknowledged by the payer).
`accepted-for-review`	A user has acknowledged the gap and marked it for follow-up or review.
`dismissed`	A user has decided the gap is not actionable (e.g., inaccurate, not relevant, or not appropriate to pursue).

RAF Scores

A RAF Score (Risk Adjustment Factor score) estimates a patient's expected healthcare cost based on demographics and diagnosed conditions. Scores are computed using CMS-HCC v28 coefficients and the Community Non-Dual Aged (CNA) model.

We calculate the following scores per patient and calendar year:

Score	Which HCCs are included
Potential	All HCCs from non-dismissed risk gaps.
Expected	Includes HCCs for gaps with an encounter diagnosis in the current measurement period.
Actual	Only HCCs from gaps with status `closed-gap` (acknowledged by payer).

Score components

Each score is the sum of:

Factor	Description
Age/sex	Demographic bracket (e.g., F70–74, M85–89) based on age as of Feb 1 of the payment year.
HCC coefficients	Weight for each HCC included in that score type.
Diagnosis count	Factors D1–D10+ based on total HCC count.
Interactions	Combination factors (e.g., Diabetes + Heart Failure).

Glossary

Term	Meaning
Risk Gap	A potential diagnosis/coding gap for a patient and calendar year, represented as a FHIR `MeasureReport`.
RAF Score	Sum of coefficients for a patient's demographics and HCCs; reflects expected cost. Includes potential, expected, and actual variants.
HCC Code	Hierarchical Condition Category code used for risk adjustment (CMS-HCC v28).
ICD-10 Code	Diagnosis code that may map to one or more HCCs. Risk gaps can track associated ICD-10 codes and provenance.
RAF Coefficient	The risk-adjustment weight associated with an HCC (and other model factors). Risk gaps store the HCC coefficient used in scoring.
Recapture	Prior-year HCC evidence exists, current-year evidence missing.
Suspect	No current/prior-year diagnosis, but evidence suggests the condition exists (rules evidence, AI suspecting, payer file, etc.).
Net-new	Current-year evidence exists, no prior-year evidence.
Encounter Diagnosis	A diagnosis recorded during a clinical encounter (represented as a FHIR `Condition` with an encounter-diagnosis category).
Evidence (evaluated vs related)	"Evaluated" means the resource was used to determine the gap; "Related" provides helpful context for reviewers.

Network Query Requirements and Constraints

Customers are welcome to run their own records through Zus’s Risk Adjustment Recapture and Suspecting logic at any time. However, all requests to CommonWell, Carequality, and Surescripts must be for the purpose of Treating a patient.

In practice, that means that your users and your Zus subscriptions can request records for the following reasons:

To chart prep for an appointment
To stratify a population and identify patients rising in risk or in need of urgent engagement
To identify patients with open care gaps
Based on Zus’s standard intelligent refresh triggers as defined here

If you have purchased the Risk Adjustment add-on, Zus will automatically enrich records you retrieve with indicators for HCCs, suspect and recaptured condition indicators, and RAF scores. You are free to use these records for risk adjustment and other secondary Payment and Operations activities.

Customers may not initiate requests to the networks purely to support reporting and audit requirements, e.g.:

End-of-year retrospective risk adjustment and evidence capture
Quarterly or annual quality reporting and evidence capture (e.g., eCQM, HEDIS)