V28 Is Coming For Your RAF Score—Here's What Internal Medicine Practices Will Actually Lose

CMS-HCC Model V28 is fully operative as of January 1, 2026 — not phasing in, not transitioning. Done. According to RAAPID Inc., V28 now drives 100% of Medicare Advantage risk scores after a three-year phased transition, and it eliminates more than 2,000 valid ICD-10-CM codes from HCC mapping in the process.

This is a revenue event. Wolters Kluwer, citing CMS official projections, puts the average RAF score decline at 3.12% industry-wide — with early real-world data from VBC Risk Analytics showing 5–30% declines at organizations that haven't adapted. Internal Medicine practices, whose panels are disproportionately loaded with diabetes, CHF, CKD, and COPD — the exact chronic conditions V28 constrained most aggressively — face above-average exposure. What follows is a practical guide to modeling that exposure and closing the gap before it compounds further.

What V28 Actually Changes — And Why Internal Medicine Takes the Hardest Hit

V28 is not a coding update. It is a structural repricing of chronic disease complexity — and Internal Medicine practices are sitting at the center of it.

The model eliminated more than 2,000 ICD-10-CM codes from HCC mapping while simultaneously tightening coefficients on the exact conditions that define the average IM panel. As RAAPID Inc. notes, "A lower score does not mean a member's health improved. It means the model now credits fewer of the conditions in the record."

The condition-level damage is specific:

• Diabetes: All diabetes HCCs now share a single coefficient of approximately 0.166 under V28. Under V24, diabetes with peripheral vascular disease carried a combined coefficient of 0.590 — according to VBC Risk Analytics, the largest single-condition revenue reduction in the new model.
• CHF: V28 now requires systolic vs. diastolic distinction, acuity level, and ejection fraction — each affecting which HCC the diagnosis maps to.
• CKD: Stage 3 now has dedicated HCC categories (328 and 329), separated from Stage 4 and Stage 5/ESRD, demanding greater specificity than most current documentation delivers.

The financial proof is already public. V28 represented a $6 billion revenue headwind for UnitedHealth Group in 2026 alone, per CNBC reporting on UnitedHealth CFO John Rex's earnings call. If that is the impact on the largest payer in the country, the per-practice math for IM panels loaded with diabetes, CKD, and CHF patients is not abstract — it is arithmetic.

Translating RAF Score Compression Into Dollar Figures Your CFO Can Work With

The math is not complicated — it is just uncomfortable. According to Invene (2025), every 0.1 drop in RAF score costs roughly $1,040 in annual revenue per Medicare Advantage member, based on the 2025 CMS base payment rate.

Run that across a 500-member MA panel with a conservative V28-driven RAF compression of 0.10–0.15:

• 0.10 RAF drop × 500 members = $520,000 in annualized revenue loss
• 0.15 RAF drop × 500 members = $780,000 in annualized revenue loss

That range is not hypothetical. VBC Risk Analytics reports that 20–35% of chronic HCC conditions fail to recapture annually under standard coding workflows — before factoring in V28's tighter specificity requirements. For an IM panel already carrying documentation habits calibrated to V24 thresholds, the compounding effect is real and immediate.

V28 is now fully operative at 100% weight in 2026. Practices still running V24-optimized documentation workflows are not just leaving revenue on the table — they are generating risk scores they cannot sustain under audit scrutiny, as the OIG's January 2026 Work Plan specifically flagged V24-versus-V28 coding patterns for heightened review, according to Doctors Management.

The grace period ended. The revenue impact did not wait for your next planning cycle.

The Documentation Gap Most IM Practices Don't Know They Have

Consider a patient you saw last quarter: Type 2 diabetes with diabetic CKD, Stage 3a, alongside hypertensive heart disease. You managed all three conditions. You renewed medications, reviewed labs, adjusted doses. But if the encounter note reads "diabetes, well-controlled" and "CKD, stable" — under V28, that documentation generates a fraction of the RAF credit the clinical picture justifies.

Under V28, Stage 3 CKD now maps to its own dedicated HCC categories (328 and 329), separated from Stage 4 and ESRD, according to HCC Buddy. Staging has to be explicit. "CKD, stable" does not get there.

The same precision gap applies to heart failure. VBC Risk Analytics confirms V28 requires systolic vs. diastolic distinction, acuity level, and ejection fraction — all documented — before CHF maps to the correct HCC category.

Multiply this across a panel of 500 Medicare Advantage patients, each carrying 3–4 chronic conditions, and the compounding effect is not marginal. According to RAAPID Inc., CMS's FY2025 Part C improper payment rate hit 6.09% — $23.67 billion — with most attributed to documentation that failed to substantiate diagnosis data. Your practice does not need to be billing fraudulently to be caught in that net. Underspecified documentation is its own liability.

• Stage 3 CKD requires documented staging — not "CKD, chronic"
• CHF requires systolic/diastolic distinction, acuity, and ejection fraction
• Diabetes with complications must specify the complication to map correctly

The V24 habits that worked two years ago are now generating either missed revenue or audit flags. Those are the only two outcomes available to a practice still documenting at V24 specificity thresholds.

What a V28-Ready Practice Looks Like — And Where Technology Closes the Gap

V28-ready practices are not defined by what they code after the visit — they are defined by what they catch during it. The encounter types that create legitimate HCC capture opportunities under V28 are already in your schedule:

• Annual Wellness Visits — the highest-yield window for chronic condition documentation and recapture
• Chronic Care Management visits — where specificity failures compound fastest across complex patients
• Transitional Care Management encounters — where post-discharge diagnoses are frequently under-specified
• Complex office visits (99214/99215) — where multi-condition patients generate the most HCC exposure per encounter

The workflow problem is not retrospective. According to VBC Risk Analytics, top-performing Medicare Advantage plans achieve 85–92% chronic condition recapture rates through continuous monitoring — versus 65–75% for annual-only programs. That gap is a direct revenue differential, measurable per patient.

The root issue is timing. Most documentation gaps are identified weeks after the encounter closes — when nothing can be fixed without an addendum that invites audit scrutiny.

Perfect Rhythm's ForeSee ESP surfaces HCC gap alerts inside the clinical workflow, before the encounter closes. Its NLP engine scans existing chart documentation, flags clinically-supported conditions that are undocumented or under-specified for V28, and links directly to the source record via InstaVu — so the physician sees the gap with evidence attached, not a vague coding suggestion.

That is the structural difference between documentation accuracy built into the visit and compliance chased after the fact.

The CBO projects Medicare Advantage will cover 63% of all Medicare beneficiaries by 2034, according to KFF citing the Congressional Budget Office. That trajectory means accurate RAF scoring under V28 is not a 2026 problem you solve once — it is the financial foundation your practice runs on for the next decade.

The risk is three-layered and compounding:

• Model compression: V28 structurally reduces RAF scores for the chronic conditions that fill IM panels — diabetes, CHF, CKD, COPD. The math does not improve by waiting.
• Documentation gaps: VBC Risk Analytics reports that top-performing Medicare Advantage plans achieve 85–92% chronic condition recapture rates through continuous monitoring. Annual-only programs land at 65–75%. The gap between those two numbers is direct revenue loss, calculated per patient, per year.
• Workflow inertia: Coding habits built for V24 do not automatically produce V28-compliant specificity. According to Inferscience, an 85% HCC recapture rate is the industry floor for financial stability — most practices are not tracking whether they hit it.

Practices that close documentation gaps now will not just protect existing reimbursement. They will capture RAF credit their current workflow is already leaving on the table.

• Schedule a RAF score impact assessment to benchmark your Medicare Advantage panel against V28 exposure
• Download the Perfect Rhythm V28 Readiness Checklist to audit your top 10 high-risk HCC categories
• Request a demo of ForeSee ESP to see automated HCC gap identification inside your existing workflow

Frequently Asked Questions

What is the CMS-HCC V28 model transition?

The CMS-HCC V28 model is the updated risk adjustment methodology CMS uses to calculate Medicare Advantage payment rates. It became fully operative on January 1, 2026, replacing V24 and reducing the number of valid ICD-10-CM codes that map to HCC categories from 9,797 to 7,770.

How does V28 affect RAF scores for Internal Medicine practices?

CMS projects an average RAF score decline of 3.12% industry-wide, but Internal Medicine practices face above-average exposure because their panels are concentrated in the chronic condition categories — diabetes, CHF, CKD, COPD — that V28 constrained most aggressively. Early data from VBC Risk Analytics shows organizations with unchanged patient populations experiencing RAF declines of 5–30%.

What happens if a practice continues coding under V24 logic after the transition?

Diagnoses submitted using V24-era code logic may no longer generate a risk score under V28 — and according to RAAPID Inc., they may also generate an audit flag. The OIG's 2026 Work Plan specifically targets trends in V24 versus V28 risk adjustment data, and unsupported codes create potential False Claims Act exposure.

How much revenue is at stake per patient with a RAF score drop?

Every 0.1 decrease in RAF score translates to approximately $1,040 in lost annual revenue per Medicare Advantage member, based on the 2025 CMS base payment rate cited by Invene. For a 500-member MA panel, a 0.15 average RAF decline represents roughly $780,000 in annualized revenue erosion.

What tools help practices close HCC documentation gaps under V28?

AI-powered NLP platforms like ForeSee ESP scan patient records across EHR systems to surface clinically documented but undercoded chronic conditions, flagging both missing HCCs and unsupported codes that create RADV audit risk. Point-of-care diagnostic tools like CorVista address underdiagnosis of cardiovascular conditions upstream — generating the clinical documentation that supports legitimate HCC capture in the first place.