V28 HCC 398Community non-dual aged RAF 0.199
Major Head Injury with Loss of Consciousness < 1 Hour or Unspecified
Under the CMS-HCC V28 risk adjustment model (PY2026 Medicare Advantage), HCC 398 carries a community non-dual aged RAF of 0.199, and 57 payable ICD-10-CM diagnosis codes map to it. In the V28 hierarchy it is superseded by HCC 397 when a more severe category in the same disease group is also present.
RAF factors
The community factor varies by Medicaid and originally-disabled status; the institutional factor applies to long-term-institutional members. These are the CMS-HCC V28 PY2026 relative factors.
Community NA: 0.199Community PBA: 0.128Community FBA: 0.349Community ND: 0.15Community PBD: 0.052Community FBD: 0.19Institutional: 0.085
V28 hierarchy
Trumped by: HCC 397 (a more severe category in the same disease group supersedes this one).
Supersedes: HCC 202, HCC 399 (this category is counted instead of these when they co-occur).
ICD-10-CM codes that map to HCC 398 (57)
Payable diagnosis codes that map to this category under CMS-HCC V28 PY2026. Open any code for its full description, HCC mapping, and coding guidance.
- S06.1X1ATraumatic cerebral edema with loss of consciousness of 30 minutes or less, initial encounter
- S06.1X2ATraumatic cerebral edema with loss of consciousness of 31 minutes to 59 minutes, initial encounter
- S06.1X9ATraumatic cerebral edema with loss of consciousness of unspecified duration, initial encounter
- S06.2X1ADiffuse traumatic brain injury with loss of consciousness of 30 minutes or less, initial encounter
- S06.2X2ADiffuse traumatic brain injury with loss of consciousness of 31 minutes to 59 minutes, initial encounter
- S06.2X9ADiffuse traumatic brain injury with loss of consciousness of unspecified duration, initial encounter
- S06.301AUnspecified focal traumatic brain injury with loss of consciousness of 30 minutes or less, initial encounter
- S06.302AUnspecified focal traumatic brain injury with loss of consciousness of 31 minutes to 59 minutes, initial encounter
- S06.309AUnspecified focal traumatic brain injury with loss of consciousness of unspecified duration, initial encounter
- S06.311AContusion and laceration of right cerebrum with loss of consciousness of 30 minutes or less, initial encounter
- S06.312AContusion and laceration of right cerebrum with loss of consciousness of 31 minutes to 59 minutes, initial encounter
- S06.319AContusion and laceration of right cerebrum with loss of consciousness of unspecified duration, initial encounter
- S06.321AContusion and laceration of left cerebrum with loss of consciousness of 30 minutes or less, initial encounter
- S06.322AContusion and laceration of left cerebrum with loss of consciousness of 31 minutes to 59 minutes, initial encounter
- S06.329AContusion and laceration of left cerebrum with loss of consciousness of unspecified duration, initial encounter
- S06.331AContusion and laceration of cerebrum, unspecified, with loss of consciousness of 30 minutes or less, initial encounter
- S06.332AContusion and laceration of cerebrum, unspecified, with loss of consciousness of 31 minutes to 59 minutes, initial encounter
- S06.339AContusion and laceration of cerebrum, unspecified, with loss of consciousness of unspecified duration, initial encounter
- S06.341ATraumatic hemorrhage of right cerebrum with loss of consciousness of 30 minutes or less, initial encounter
- S06.342ATraumatic hemorrhage of right cerebrum with loss of consciousness of 31 minutes to 59 minutes, initial encounter
- S06.349ATraumatic hemorrhage of right cerebrum with loss of consciousness of unspecified duration, initial encounter
- S06.351ATraumatic hemorrhage of left cerebrum with loss of consciousness of 30 minutes or less, initial encounter
- S06.352ATraumatic hemorrhage of left cerebrum with loss of consciousness of 31 minutes to 59 minutes, initial encounter
- S06.359ATraumatic hemorrhage of left cerebrum with loss of consciousness of unspecified duration, initial encounter
- S06.361ATraumatic hemorrhage of cerebrum, unspecified, with loss of consciousness of 30 minutes or less, initial encounter
- S06.362ATraumatic hemorrhage of cerebrum, unspecified, with loss of consciousness of 31 minutes to 59 minutes, initial encounter
- S06.369ATraumatic hemorrhage of cerebrum, unspecified, with loss of consciousness of unspecified duration, initial encounter
- S06.371AContusion, laceration, and hemorrhage of cerebellum with loss of consciousness of 30 minutes or less, initial encounter
- S06.372AContusion, laceration, and hemorrhage of cerebellum with loss of consciousness of 31 minutes to 59 minutes, initial encounter
- S06.379AContusion, laceration, and hemorrhage of cerebellum with loss of consciousness of unspecified duration, initial encounter
- S06.381AContusion, laceration, and hemorrhage of brainstem with loss of consciousness of 30 minutes or less, initial encounter
- S06.382AContusion, laceration, and hemorrhage of brainstem with loss of consciousness of 31 minutes to 59 minutes, initial encounter
- S06.389AContusion, laceration, and hemorrhage of brainstem with loss of consciousness of unspecified duration, initial encounter
- S06.4X1AEpidural hemorrhage with loss of consciousness of 30 minutes or less, initial encounter
- S06.4X2AEpidural hemorrhage with loss of consciousness of 31 minutes to 59 minutes, initial encounter
- S06.4X9AEpidural hemorrhage with loss of consciousness of unspecified duration, initial encounter
- S06.5X1ATraumatic subdural hemorrhage with loss of consciousness of 30 minutes or less, initial encounter
- S06.5X2ATraumatic subdural hemorrhage with loss of consciousness of 31 minutes to 59 minutes, initial encounter
- S06.5X9ATraumatic subdural hemorrhage with loss of consciousness of unspecified duration, initial encounter
- S06.6X1ATraumatic subarachnoid hemorrhage with loss of consciousness of 30 minutes or less, initial encounter
- S06.6X2ATraumatic subarachnoid hemorrhage with loss of consciousness of 31 minutes to 59 minutes, initial encounter
- S06.6X9ATraumatic subarachnoid hemorrhage with loss of consciousness of unspecified duration, initial encounter
- S06.811AInjury of right internal carotid artery, intracranial portion, not elsewhere classified with loss of consciousness of 30 minutes or less, initial encounter
- S06.812AInjury of right internal carotid artery, intracranial portion, not elsewhere classified with loss of consciousness of 31 minutes to 59 minutes, initial encounter
- S06.819AInjury of right internal carotid artery, intracranial portion, not elsewhere classified with loss of consciousness of unspecified duration, initial encounter
- S06.821AInjury of left internal carotid artery, intracranial portion, not elsewhere classified with loss of consciousness of 30 minutes or less, initial encounter
- S06.822AInjury of left internal carotid artery, intracranial portion, not elsewhere classified with loss of consciousness of 31 minutes to 59 minutes, initial encounter
- S06.829AInjury of left internal carotid artery, intracranial portion, not elsewhere classified with loss of consciousness of unspecified duration, initial encounter
- S06.891AOther specified intracranial injury with loss of consciousness of 30 minutes or less, initial encounter
- S06.892AOther specified intracranial injury with loss of consciousness of 31 minutes to 59 minutes, initial encounter
- S06.899AOther specified intracranial injury with loss of consciousness of unspecified duration, initial encounter
- S06.8A1APrimary blast injury of brain, not elsewhere classified with loss of consciousness of 30 minutes or less, initial encounter
- S06.8A2APrimary blast injury of brain, not elsewhere classified with loss of consciousness of 31 minutes to 59 minutes, initial encounter
- S06.8A9APrimary blast injury of brain, not elsewhere classified with loss of consciousness of unspecified duration, initial encounter
- S06.9X1AUnspecified intracranial injury with loss of consciousness of 30 minutes or less, initial encounter
- S06.9X2AUnspecified intracranial injury with loss of consciousness of 31 minutes to 59 minutes, initial encounter
- S06.9X9AUnspecified intracranial injury with loss of consciousness of unspecified duration, initial encounter
Frequently asked questions
What is CMS-HCC V28 category 398?
HCC 398 is "Major Head Injury with Loss of Consciousness < 1 Hour or Unspecified", a payment Hierarchical Condition Category in the CMS-HCC V28 risk adjustment model (100% phase-in for payment year 2026). 57 payable ICD-10-CM codes map to it.
What is the RAF weight for HCC 398?
The community non-dual aged relative factor for CMS-HCC V28 category 398 is 0.199. The exact factor varies by enrollment segment (community Medicaid and originally-disabled status, and institutional); the full segment table is published in the CMS V28 Rate Announcement.
How many ICD-10-CM codes map to HCC 398?
57 payable ICD-10-CM diagnosis codes map to CMS-HCC V28 category 398 (Major Head Injury with Loss of Consciousness < 1 Hour or Unspecified) for payment year 2026.
Which categories trump HCC 398 in the V28 hierarchy?
HCC 398 is superseded by HCC 397 (Major Head Injury with Loss of Consciousness > 1 Hour). When a more severe category in the same disease group is documented, it is counted instead of HCC 398.
Source: CMS published ICD-10-CM mapping file plus CMS-HCC v28 PY2026 model software.