CONTEMPERARAY ASSESSMENT OF mTBI

Acute Clinical Assessment

Initial evaluation of suspected traumatic brain injury (TBI) commonly relies on the Glasgow Coma Scale (GCS) in combination with clinical features such as pupillary reactivity and computed tomography (CT) findings. These tools are effective for identifying severe injury and ruling out life-threatening intracranial pathology, but they are not designed to diagnose mild TBI (mTBI) or concussion, where structural imaging is frequently normal¹,². As a result, diagnostic confidence for mTBI remains limited in acute care settings.

Recovery and Persistent Symptoms

Although the majority of individuals with mTBI recover within days to weeks, a clinically meaningful minority—estimated at 10–20%—experience persistent post-concussive symptoms, including reduced functional capacity, emotional dysregulation, cognitive complaints, and delayed return to work or school³. These prolonged outcomes contribute disproportionately to healthcare utilisation and socioeconomic burden.

Post-Traumatic Amnesia (PTA)–Based Tools

A range of tools have been developed to assess cognitive disturbance following TBI, particularly post-traumatic amnesia (PTA). These include the Galveston Orientation and Amnesia Test (GOAT), the Modified Oxford PTA Scale (MOPTAS), and the Westmead Post-Traumatic Amnesia Scale (WPTAS) and Revised-WPTAS⁴–⁶. PTA duration is widely used as a prognostic indicator, particularly in moderate to severe TBI.

However, PTA represents only one component of the broader post-TBI syndrome, which may also include attentional deficits, executive dysfunction, behavioural disturbance, and agitation⁷. Many PTA tools do not comprehensively assess these domains, and evidence supporting their validity—particularly in mild or complex presentations—remains limited⁸.

Additional limitations include retrospective questioning, unverifiable responses, task difficulty that may challenge even uninjured controls, and practical constraints in emergency department environments⁸,⁹.

Neuroimaging Decision Rules

Clinical decision rules such as the Canadian CT Head Rule (CCHR) and the New Orleans Criteria (NOC) are widely used to determine the need for CT imaging after head injury¹⁰,¹¹. These tools are effective for identifying patients at risk of clinically significant intracranial injury, but they do not diagnose concussion or predict functional recovery, and their applicability is limited in specific populations (e.g. anticoagulated patients, children, non-traumatic presentations).

Military and Sports-Specific Screening Tools

In military settings, the Military Acute Concussion Evaluation (MACE) has been used since 2006 as a frontline screening tool. While operationally valuable, MACE relies on subjective symptom reporting and recall, is affected by fatigue and stress, and demonstrates reduced sensitivity when administered beyond 12–24 hours post-injury, limiting its ability to objectively confirm brain injury¹²,¹³.

In sport, the Sport Concussion Assessment Tool (SCAT6)—updated following the 6th International Consensus on Concussion in Sport—is the current standardised sideline assessment for athletes aged ≥13 years, with a Child SCAT for younger athletes¹⁴. SCAT6 provides a structured clinical framework but remains a screening tool, not a diagnostic test, and is not intended to be used in isolation for return-to-play decisions.

Summary of the Current Gap

Across civilian, military, and sporting contexts, existing tools are valuable for triage and risk stratification, but they remain subjective and indirect proxies of injury. None provide objective biological confirmation, nor are they well suited to detecting sub-concussive, repetitive, or blast-related injury. This persistent gap underpins growing interest in biologically grounded diagnostic approaches to complement clinical assessment and improve decision-making across the TBI continuum.

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