What Is the New TBI Diagnostic Framework?
For decades, traumatic brain injuries (TBIs) were diagnosed using a broad three-tier system—mild, moderate, or severe. While familiar, this approach often oversimplified complex injuries and left countless patients with lingering symptoms that went underdiagnosed or untreated. In response, leading neurologists and researchers from around the world collaborated with the National Institute of Neurological Disorders and Stroke (NINDS) to develop a more accurate and comprehensive classification system. Unveiled in early 2024, this new diagnostic framework represents the most significant advancement in brain injury diagnosis in over 50 years.
Unlike the old model, the new system uses a multi-dimensional approach to assess brain trauma through four distinct pillars: Clinical Assessment, Blood-Based Biomarkers, Imaging, and Modifiers. Clinical Assessment focuses on detailed neurological exams, including Glasgow Coma Scale scoring and symptom tracking. Blood-Based Biomarkers use advanced laboratory tests to detect brain injury that might not appear on a scan. Imaging includes CT and MRI scans to identify structural damage, bleeding, or swelling. Finally, Modifiers account for individual patient factors—like age, mental health, or social environment—that influence how a brain injury presents and heals. Together, these pillars provide a comprehensive picture of TBI severity and guide more personalized, effective treatment plans.
The 4 pillars: The New TBI Classification System
The new framework proposed by the National Institute of Neurological Disorders and Stroke (NINDS) in January 2024 introduces the CBI-M system, which incorporates four key components: Clinical, Biomarkers, Imaging, and Modifiers.
Pillar 1: Clinical Assessment
The Clinical Assessment building block speaks to the role of clinical assessment on Days 1 through 14. This group recommends that core clinical information be collected and recorded for all patients who present to a hospital with TBI.
Key Components:
- Full Glasgow Coma Scale (GCS) scoring: The clinically actionable recommendations must go beyond the conventional GCS classification into three categories to the full spectrum of GCS, specifying the component scores of motor, verbal, and eyes, while noting confounds that could impact the score.
- Pupil reactivity assessment as an indication of brain function
- Symptom evaluation including headache, dizziness, sensitivity to noise, and amnesia
- Dynamic assessment recognizing that clinical status can change over time
Pillar 2: Blood-Based Biomarkers
The Blood-Based Biomarkers pillar focuses on select biomarkers for specific use cases in certain settings at specified time points. In certain cases, including among TBI patients who do not receive a CT scan, certain blood-based biomarkers may suggest clinically important brain injury that may not show positive finding on a CT.
- Detection of invisible damage: Identifying brain tissue injury even when imaging appears normal
- Enhanced sensitivity: One of the benefits of using biomarkers to classify or categorize patients is the added sensitivity they offer, particularly among the “mildest of the mild” injuries, such as in patients with a GCS between 13-15 and negative MRI and CT
- Predicting deterioration: Potential to predict the onset or harbinger of Neuroworsening.
- Military-developed technology: Advanced blood tests that can reveal brain trauma not visible on traditional scans
Pillar 3: Imaging
The Imaging pillar addresses the importance of the role of scans such as CT and MRI in diagnosing and categorizing brain injury. The working group focusing on imaging noted the need to strike a balance between the pragmatic usefulness of CT scans with the increased sensitivity of an MRI.
Strategic Approach:
- CT scans for acute assessment: Primary imaging modality within the first 24 hours of injury
- MRI for enhanced sensitivity: More detailed detection of brain abnormalities when clinically indicated
- Selective use: This pillar focuses on CT, the most widely used imaging modality within the first 24 h of injury, but recognizes that MRI is more sensitive than CT and can provide additional information while acknowledging certain practicalities around its use in the acute phase.
- Surgical decision-making: Identifying bleeding, clots, and fractures that could be life-threatening
Pillar 4: Modifiers
The final pillar in the proposed new classification framework is focused on a biopsychosocial model – preinjury characteristics of the patient that could affect recovery, such as age or history of prior injuries, psychological factors such as the response to trauma or rehabilitation, and social and environmental factors such as the patient’s social support system, geography, and access to care.
Three Categories of Modifiers:
- Pre-injury characteristics: Age, sex, prior head injuries, medical history
- Psychological factors: Mental health status, response to trauma, rehabilitation engagement
- Social/Environmental factors: Support system, geography, access to healthcare, living circumstances
“This pillar summarizes the factors that research tells us need to be considered when we interpret a patient’s clinical, blood biomarker, and neuroimaging exams.
Knowledge-to-Practice Chart
| Clinical | Blood-Based Biomarkers | Imaging | Modifiers |
|---|---|---|---|
| Ensure Glasgow Coma Scale (GCS) assessment records eye, motor, and verbal components; pupillary reactivity; and post-traumatic amnesia | Establish insurance support for routine biomarker analysis | Standardize TBI imaging terminology and reporting | Record psychosocial and environmental modifiers (PEFs) affecting assessment of TBI severity and outcome |
| Assess and record social, medical, and injury-related factors influencing GCS/TBI outcomes | Include biomarkers in TBI practice guidelines | Use simple language to explain TBI imaging to patients and families | Research of PEFs contribute to TBI healthcare seeking, presentation, and outcome |
| Repeat symptom severity assessment for up to 14 days | Include TBI biomarker tests in acute TBI evaluation and management | Identify a core set of TBI imaging features for use in research | Develop and validate tools for measuring PEFs |
Implementation Status
The proposed framework is being phased in at trauma centers on a trial basis. It will be refined and validated before it is fully implemented. This gradual rollout ensures that the system can be tested and improved before widespread adoption across healthcare systems.
This comprehensive four-pillar approach represents a move away from the current TBI classification system, which categorizes patients as having sustained “mild,” “moderate,” or “severe” TBI, has been criticized as outdated, inaccurate, and ineffective for serving patients, clinicians, or payers.
Key Takeaways from the New TBI Framework
- Comprehensive Clinical Exams Are Now Standard
Doctors now use a detailed scoring system to assess verbal, motor, and eye responses. They also measure pupil function, loss of consciousness, and early symptoms like dizziness and confusion. - Biomarker Blood Tests Detect Invisible Damage
New military-developed blood tests can reveal brain tissue injury even when imaging looks normal. This helps avoid unnecessary CT scans and ensures timely treatment. - CT/MRI Imaging Targets Surgical Emergencies
When indicated, scans reveal bleeding, clots, and fractures that could be life-threatening. Imaging now plays a more selective and strategic role in treatment decisions. - Patient History Now Shapes Prognosis
A full review of the patient’s age, sex, prior head injuries, mental health, and support system helps predict recovery time and tailor care more effectively.
Improved Data Helps Clinical Trials and Lawsuits
By classifying patients more accurately, researchers can run better trials, and attorneys can present more convincing evidence in personal injury and malpractice cases.
Why This Matters for Injury Victims
In the U.S., traumatic brain injuries caused nearly 70,000 deaths in 2021, according to the CDC. Each year, hundreds of thousands more live with chronic symptoms—headaches, vision problems, mood changes—because their injuries were never properly diagnosed or treated.
Under the old system, a patient labeled with a “mild TBI” might have been told to rest for a few days. Weeks later, they’re still struggling with vision problems, insomnia, and anxiety. This new system prevents those experiences from being dismissed.
TBI Fatalities by Year and Month (U.S.)
As seen in the data, fatal TBIs remain a significant public health concern, with thousands of deaths reported monthly across all recent years. New diagnostic tools are essential to change this trajectory.
What to Ask Your Doctor After a Head Injury
- Did you perform a detailed clinical exam using the Glasgow Coma Scale and pupil response?
- Were biomarker blood tests considered to rule out invisible damage?
- Should we request CT or MRI imaging based on symptoms or test results?
- Can we review my medical and social history to understand recovery expectations?
- Is my current TBI classification up to date with the new framework?
If these questions aren’t being addressed, seek a second opinion or speak with a legal advocate.
Legal Impact Why Diagnosis Matters in Injury Claims
Improved diagnostic precision allows attorneys to better prove the extent of harm in personal injury cases. Misclassified TBIs can lead to insurance claim denials, delayed treatment, or even wrongful death. This framework supports stronger medical records that hold up in court.
(FAQ) Frequently Asked Questions
What is the new TBI diagnostic framework?
It’s a four-part system that combines clinical exams, biomarker tests, imaging, and personal history to provide a more accurate assessment of brain injuries.
Is this update being used in all hospitals?
Not yet. It’s currently being phased in across major trauma centers, with gradual expansion expected in the coming years.
What if my TBI wasn’t diagnosed properly years ago?
You may still qualify for a legal review. A second opinion or updated evaluation could uncover lasting damage that wasn’t originally documented.
How does this affect legal claims?
More accurate medical records can prove the full extent of injury, making it easier to win compensation in personal injury or malpractice lawsuits.
Should I request biomarker testing or advanced imaging?
Yes—especially if your symptoms persist or worsen. These tools help confirm or rule out hidden brain damage.