CMS-HCC Risk Adjustment · V28 Model · Payment Year 2026 57 Codes

HCC 398: Major Head Injury with Loss of Consciousness < 1 Hour or Unspecified ICD-10-CM

Q: What is the RAF weight for HCC 398?

For payment year 2026, HCC 398 adds 0.199 to the RAF score of a community, non-dual, aged beneficiary. The published weights range from 0.052 to 0.349 across the seven payment segments shown above.

Q: Which categories supersede HCC 398?

HCC 397 (Major Head Injury with Loss of Consciousness > 1 Hour) sits above HCC 398 in the hierarchy: when a beneficiary has diagnoses in both, only the more severe category is paid.

CMS-HCC Category 398 (Major Head Injury with Loss of Consciousness < 1 Hour or Unspecified) is a payment HCC in the V28 Medicare Advantage risk adjustment model. For payment year 2026 it adds a risk adjustment factor between 0.052 and 0.349 to a beneficiary's RAF score depending on the payment segment (0.199 for a community, non-dual, aged enrollee). 57 ICD-10-CM diagnosis codes map to HCC 398. A more severe related category (HCC 397) supersedes it when both are reported.

✓ Built from the official CMS PY 2026 risk adjustment filesV28 pays 100% of MA risk scores from PY 2026

+0.199

RAF, Community Non-Dual Aged

ICD-10-CM Codes

HCC 397

Superseded By

PY 2026

Dataset

CMS-HCC V28

RAF Weight by Payment Segment 7 segments

Payment Segment	Relative Factor
Community, non-dual, aged	0.199
Community, partial-benefit dual, aged	0.128
Community, full-benefit dual, aged	0.349
Community, non-dual, disabled	0.150
Community, partial-benefit dual, disabled	0.052
Community, full-benefit dual, disabled	0.190
Institutional	0.085

A beneficiary is scored in exactly one segment, set by Medicaid (dual) status, aged or disabled entitlement, and residence. Factors are relative weights, not dollar amounts; new-enrollee segments score on demographics only. In the hierarchy, HCC 397 (Major Head Injury with Loss of Consciousness > 1 Hour) supersedes HCC 398 when reported together. HCC 398 in turn supersedes HCC 202 (Coma, Brain Compression/Anoxic Damage) and HCC 399 (Major Head Injury without Loss of Consciousness).

ICD-10-CM

ICD-10-CM Codes That Map to HCC 398 57 codes

57 of 57 shown

S06.1X1A Traumatic cerebral edema with loss of consciousness of 30 minutes or less, initial encounter from V24 HCC 167
S06.1X2A Traumatic cerebral edema with loss of consciousness of 31 minutes to 59 minutes, initial encounter from V24 HCC 167
S06.1X9A Traumatic cerebral edema with loss of consciousness of unspecified duration, initial encounter from V24 HCC 167
S06.2X1A Diffuse traumatic brain injury with loss of consciousness of 30 minutes or less, initial encounter from V24 HCC 167
S06.2X2A Diffuse traumatic brain injury with loss of consciousness of 31 minutes to 59 minutes, initial encounter from V24 HCC 167
S06.2X9A Diffuse traumatic brain injury with loss of consciousness of unspecified duration, initial encounter from V24 HCC 167
S06.301A Unspecified focal traumatic brain injury with loss of consciousness of 30 minutes or less, initial encounter from V24 HCC 167
S06.302A Unspecified focal traumatic brain injury with loss of consciousness of 31 minutes to 59 minutes, initial encounter from V24 HCC 167
S06.309A Unspecified focal traumatic brain injury with loss of consciousness of unspecified duration, initial encounter from V24 HCC 167
S06.311A Contusion and laceration of right cerebrum with loss of consciousness of 30 minutes or less, initial encounter from V24 HCC 167
S06.312A Contusion and laceration of right cerebrum with loss of consciousness of 31 minutes to 59 minutes, initial encounter from V24 HCC 167
S06.319A Contusion and laceration of right cerebrum with loss of consciousness of unspecified duration, initial encounter from V24 HCC 167
S06.321A Contusion and laceration of left cerebrum with loss of consciousness of 30 minutes or less, initial encounter from V24 HCC 167
S06.322A Contusion and laceration of left cerebrum with loss of consciousness of 31 minutes to 59 minutes, initial encounter from V24 HCC 167
S06.329A Contusion and laceration of left cerebrum with loss of consciousness of unspecified duration, initial encounter from V24 HCC 167
S06.331A Contusion and laceration of cerebrum, unspecified, with loss of consciousness of 30 minutes or less, initial encounter from V24 HCC 167
S06.332A Contusion and laceration of cerebrum, unspecified, with loss of consciousness of 31 minutes to 59 minutes, initial encounter from V24 HCC 167
S06.339A Contusion and laceration of cerebrum, unspecified, with loss of consciousness of unspecified duration, initial encounter from V24 HCC 167
S06.341A Traumatic hemorrhage of right cerebrum with loss of consciousness of 30 minutes or less, initial encounter from V24 HCC 167
S06.342A Traumatic hemorrhage of right cerebrum with loss of consciousness of 31 minutes to 59 minutes, initial encounter from V24 HCC 167
S06.349A Traumatic hemorrhage of right cerebrum with loss of consciousness of unspecified duration, initial encounter from V24 HCC 167
S06.351A Traumatic hemorrhage of left cerebrum with loss of consciousness of 30 minutes or less, initial encounter from V24 HCC 167
S06.352A Traumatic hemorrhage of left cerebrum with loss of consciousness of 31 minutes to 59 minutes, initial encounter from V24 HCC 167
S06.359A Traumatic hemorrhage of left cerebrum with loss of consciousness of unspecified duration, initial encounter from V24 HCC 167
S06.361A Traumatic hemorrhage of cerebrum, unspecified, with loss of consciousness of 30 minutes or less, initial encounter from V24 HCC 167
S06.362A Traumatic hemorrhage of cerebrum, unspecified, with loss of consciousness of 31 minutes to 59 minutes, initial encounter from V24 HCC 167
S06.369A Traumatic hemorrhage of cerebrum, unspecified, with loss of consciousness of unspecified duration, initial encounter from V24 HCC 167
S06.371A Contusion, laceration, and hemorrhage of cerebellum with loss of consciousness of 30 minutes or less, initial encounter from V24 HCC 167
S06.372A Contusion, laceration, and hemorrhage of cerebellum with loss of consciousness of 31 minutes to 59 minutes, initial encounter from V24 HCC 167
S06.379A Contusion, laceration, and hemorrhage of cerebellum with loss of consciousness of unspecified duration, initial encounter from V24 HCC 167
S06.381A Contusion, laceration, and hemorrhage of brainstem with loss of consciousness of 30 minutes or less, initial encounter from V24 HCC 167
S06.382A Contusion, laceration, and hemorrhage of brainstem with loss of consciousness of 31 minutes to 59 minutes, initial encounter from V24 HCC 167
S06.389A Contusion, laceration, and hemorrhage of brainstem with loss of consciousness of unspecified duration, initial encounter from V24 HCC 167
S06.4X1A Epidural hemorrhage with loss of consciousness of 30 minutes or less, initial encounter from V24 HCC 167
S06.4X2A Epidural hemorrhage with loss of consciousness of 31 minutes to 59 minutes, initial encounter from V24 HCC 167
S06.4X9A Epidural hemorrhage with loss of consciousness of unspecified duration, initial encounter from V24 HCC 167
S06.5X1A Traumatic subdural hemorrhage with loss of consciousness of 30 minutes or less, initial encounter from V24 HCC 167
S06.5X2A Traumatic subdural hemorrhage with loss of consciousness of 31 minutes to 59 minutes, initial encounter from V24 HCC 167
S06.5X9A Traumatic subdural hemorrhage with loss of consciousness of unspecified duration, initial encounter from V24 HCC 167
S06.6X1A Traumatic subarachnoid hemorrhage with loss of consciousness of 30 minutes or less, initial encounter from V24 HCC 167
S06.6X2A Traumatic subarachnoid hemorrhage with loss of consciousness of 31 minutes to 59 minutes, initial encounter from V24 HCC 167
S06.6X9A Traumatic subarachnoid hemorrhage with loss of consciousness of unspecified duration, initial encounter from V24 HCC 167
S06.811A Injury of right internal carotid artery, intracranial portion, not elsewhere classified with loss of consciousness of 30 minutes or less, initial encounter from V24 HCC 167
S06.812A Injury of right internal carotid artery, intracranial portion, not elsewhere classified with loss of consciousness of 31 minutes to 59 minutes, initial encounter from V24 HCC 167
S06.819A Injury of right internal carotid artery, intracranial portion, not elsewhere classified with loss of consciousness of unspecified duration, initial encounter from V24 HCC 167
S06.821A Injury of left internal carotid artery, intracranial portion, not elsewhere classified with loss of consciousness of 30 minutes or less, initial encounter from V24 HCC 167
S06.822A Injury of left internal carotid artery, intracranial portion, not elsewhere classified with loss of consciousness of 31 minutes to 59 minutes, initial encounter from V24 HCC 167
S06.829A Injury of left internal carotid artery, intracranial portion, not elsewhere classified with loss of consciousness of unspecified duration, initial encounter from V24 HCC 167
S06.891A Other specified intracranial injury with loss of consciousness of 30 minutes or less, initial encounter from V24 HCC 167
S06.892A Other specified intracranial injury with loss of consciousness of 31 minutes to 59 minutes, initial encounter from V24 HCC 167
S06.899A Other specified intracranial injury with loss of consciousness of unspecified duration, initial encounter from V24 HCC 167
S06.8A1A Primary blast injury of brain, not elsewhere classified with loss of consciousness of 30 minutes or less, initial encounter from V24 HCC 167
S06.8A2A Primary blast injury of brain, not elsewhere classified with loss of consciousness of 31 minutes to 59 minutes, initial encounter from V24 HCC 167
S06.8A9A Primary blast injury of brain, not elsewhere classified with loss of consciousness of unspecified duration, initial encounter from V24 HCC 167
S06.9X1A Unspecified intracranial injury with loss of consciousness of 30 minutes or less, initial encounter from V24 HCC 167
S06.9X2A Unspecified intracranial injury with loss of consciousness of 31 minutes to 59 minutes, initial encounter from V24 HCC 167
S06.9X9A Unspecified intracranial injury with loss of consciousness of unspecified duration, initial encounter from V24 HCC 167

Every code above carries the full HCC 398 weight when documented and reported on a Medicare Advantage encounter. The code link opens its full page with the complete risk adjustment card.

Questions About HCC 398

What is HCC 398 in the CMS-HCC model?

HCC 398 is CMS-HCC Category 398 (Major Head Injury with Loss of Consciousness < 1 Hour or Unspecified) in the V28 risk adjustment model. It covers 57 ICD-10-CM diagnosis codes that raise a Medicare Advantage beneficiary's risk score when documented.

What is the RAF weight for HCC 398?

For payment year 2026, HCC 398 adds 0.199 to the RAF score of a community, non-dual, aged beneficiary. The published weights range from 0.052 to 0.349 across the seven payment segments shown above.

Which categories supersede HCC 398?

HCC 397 (Major Head Injury with Loss of Consciousness > 1 Hour) sits above HCC 398 in the hierarchy: when a beneficiary has diagnoses in both, only the more severe category is paid.

Related References

All HCC Categories HCC 397 Codes HCC 202 Codes HCC 399 Codes V24 to V28: What Changed ICD-10-CM Code Lookup

Source: Centers for Medicare & Medicaid Services, Payment Year 2026 risk adjustment mapping and model software releases (CMS-HCC V28), applied to the FY 2026 ICD-10-CM code set. ICD List is not affiliated with CMS.