For Doctors in a Hurry
- Researchers sought to streamline the 22-item Sport Concussion Assessment Tool symptom list to improve diagnostic accuracy and clinical efficiency.
- This prospective cohort study evaluated 59,901 collegiate athletes and military cadets, including 5,075 individuals diagnosed with an acute concussion.
- The 6-item mini Symptom Index Tool achieved an area under the curve of 0.94, with 87 percent sensitivity and 88 percent specificity.
- Combining the index with vestibular and ocular motor screening increased specificity to 92 percent, while other neuropsychological tests provided no additional diagnostic utility.
- Clinicians can use a cut-off score of two or higher on both assessments to identify concussions more accurately than longer traditional surveys.
The clinical diagnosis of sport-related concussion remains a significant challenge for frontline physicians because there is no objective gold standard for identifying the injury [1]. Current consensus guidelines emphasize a multimodal assessment strategy that incorporates symptom reports, cognitive testing, and balance evaluations, yet the utility of these tools often diminishes rapidly within the first week post-injury [2, 3]. While the Sport Concussion Assessment Tool has served as the standard framework for nearly two decades, clinicians frequently encounter heterogeneity in patient presentations, ranging from migraine-like clusters to vestibular and cognitive-emotional subtypes [4, 5]. Emerging evidence suggests that incorporating specific assessments of the vestibular and ocular motor systems may provide higher diagnostic value than traditional static balance tests [6, 7]. A large-scale analysis now evaluates whether a more targeted symptom profile can improve diagnostic accuracy over existing comprehensive checklists, potentially streamlining sideline and clinic evaluations.
Large-Scale Validation Within the CARE Consortium
To evaluate the diagnostic utility of various assessment tools in the acute phase of injury, researchers conducted a prospective cohort study utilizing data from the National Collegiate Athletic Association-Department of Defense Concussion Assessment Research and Education (CARE) Consortium. This massive investigation enrolled 59,901 athletes and cadets from collegiate athletics programs and military service academies. Within this cohort, 5,075 individuals were diagnosed with a concussion, providing a robust dataset to compare clinical presentations against non-concussed peers. The primary objective was to analyze assessments performed within 48 hours of injury to determine which specific symptoms and tests offered the highest diagnostic weight. The analysis compared concussed versus non-concussed individuals using a comprehensive battery of established diagnostic instruments. These included the Sport Concussion Assessment Tool (SCAT) 22-item symptom survey, the Standardised Assessment of Concussion (a brief cognitive screening tool), and the modified Balance Error Scoring System (a measure of postural stability). To identify which examinations provided the most additive value, the researchers also evaluated the modified Vestibular/Ocular Motor Screening (mVOMS), an assessment of symptoms provoked by eye movements and balance challenges, alongside the Immediate Post-Concussion Assessment and Cognitive Testing, a computerized neuropsychological battery. Furthermore, the study incorporated the King-Devick test (a rapid eye-movement task), Clinical Reaction Time, and numerous other neuropsychological tests to isolate the most effective diagnostic indicators.
Identifying High-Yield Symptoms and Effect Sizes
The researchers analyzed the diagnostic weight of individual symptoms by calculating Cohen’s d effect sizes, a statistical measure that quantifies the magnitude of the difference between the concussed and non-concussed groups. While the standard 22-item symptom survey covers a broad range of physical and cognitive complaints, the individual symptoms demonstrated a wide variety of effect sizes. The analysis revealed that headache demonstrated the largest individual effect size at d=2.85, identifying it as the most potent single indicator of acute injury in this cohort. This was followed closely by pressure in head, which showed an effect size of d=2.59, and the subjective report that the patient does not feel right, which demonstrated an effect size of d=2.51. These high effect sizes suggest that these specific symptoms provide the most significant clinical utility when differentiating concussed athletes and cadets from their healthy peers within the first 48 hours of injury. Beyond individual symptoms, the study compared the diagnostic strength of various clinical examinations. The standard Symptom Severity Score, which aggregates all 22 items on the SCAT, yielded an effect size of d=2.09. However, the modified Vestibular/Ocular Motor Screening (mVOMS) demonstrated the largest examination effect size at d=3.41, significantly exceeding the diagnostic magnitude of the traditional symptom checklist. This screening tool, which evaluates the vestibular system and ocular motor function through tasks such as smooth pursuits and saccades, proved to be the most robust objective measure for identifying acute concussion. For the practicing clinician, these findings emphasize that while a comprehensive symptom report is valuable, focusing on high-yield symptoms and incorporating a brief vestibular screen can substantially increase the statistical certainty of a concussion diagnosis.
To streamline the clinical assessment of acute concussion, the researchers developed the mini Symptom Index Tool (mSIT). This instrument focuses on six high-yield symptoms: headache, pressure in head, do not feel right, sensitivity to light, dizziness, and sensitivity to noise. Each symptom is evaluated using a 7-point Likert scale, a standardized psychometric tool where patients rate the severity of their symptoms from 0 to 6. The mini Symptom Index Tool is calculated as the sum of these six scores, resulting in a total score range of 0 to 36. By isolating these specific indicators, the tool aims to provide a more targeted diagnostic focus than the traditional 22-item checklist used in the SCAT. The diagnostic performance of the mini Symptom Index Tool was evaluated using the area under the curve (AUC), a statistical metric representing the probability that the test will correctly distinguish a concussed patient from a healthy one. The standard SCAT symptom severity index demonstrated an AUC of 0.88, with a sensitivity of 85% and a specificity of 76%. In comparison, the mini Symptom Index Tool alone achieved an AUC of 0.94, a sensitivity of 87%, and a specificity of 88%. These findings indicate that the 6-item tool provides a more accurate diagnostic profile than the 22-item version, specifically offering a 12% improvement in specificity. For physicians, this higher specificity directly translates to a reduced likelihood of false-positive diagnoses in a busy clinical setting.
Clinical Utility of the mSIT Plus Protocol
While the mini Symptom Index Tool provides a robust diagnostic foundation, the researchers identified the modified Vestibular/Ocular Motor Screening (mVOMS) as the only examination that provided additional diagnostic utility. When these two assessments are combined into a protocol termed mSIT Plus, the diagnostic accuracy reaches an area under the curve of 0.94, with a sensitivity of 88% and a specificity of 92%. This high specificity is particularly relevant for clinicians who must distinguish acute concussion from other conditions or baseline symptoms in athletes and cadets within the first 48 hours of injury. To implement this protocol in a clinical setting, the study proposes specific thresholds for identifying injury. The clinical cut-off score for the mini Symptom Index Tool is 2 or higher, and the proposed clinical cut-off score for the modified Vestibular/Ocular Motor Screening is also 2 or higher. Notably, the researchers found that all other examinations evaluated within the CARE Consortium were non-additive in the identification of acute concussion. These non-contributory assessments included the Standardised Assessment of Concussion, the modified Balance Error Scoring System, the King-Devick test, Clinical Reaction Time, and various neuropsychological tests, as well as the Immediate Post-Concussion Assessment and Cognitive Testing. The primary advantage of the mSIT Plus protocol for the practicing physician is its clinical efficiency without a loss of diagnostic precision. The entire mSIT Plus evaluation, consisting of both the 6-item symptom index and the modified Vestibular/Ocular Motor Screening, can be completed within 2 to 3 minutes. This streamlined approach allows for rapid, evidence-based assessment in high-volume environments like training rooms or clinics, focusing only on the metrics that statistically contribute to an accurate diagnosis in the acute window following a suspected head injury.
References
1. Feddermann‐Demont N, Echemendía RJ, Schneider K, et al. What domains of clinical function should be assessed after sport-related concussion? A systematic review. British Journal of Sports Medicine. 2017. doi:10.1136/bjsports-2016-097403
2. Echemendía RJ, Burma JS, Bruce JM, et al. Acute evaluation of sport-related concussion and implications for the Sport Concussion Assessment Tool (SCAT6) for adults, adolescents and children: a systematic review. British Journal of Sports Medicine. 2023. doi:10.1136/bjsports-2022-106661
3. Patricios J, Schneider K, Dvořák J, et al. Consensus statement on concussion in sport: the 6th International Conference on Concussion in Sport–Amsterdam, October 2022. British Journal of Sports Medicine. 2023. doi:10.1136/bjsports-2023-106898
4. Langdon S, Königs M, Adang EAMC, Goedhart EA, Oosterlaan J. Subtypes of Sport-Related Concussion: a Systematic Review and Meta-cluster Analysis. Sports Medicine. 2020. doi:10.1007/s40279-020-01321-9
5. Terry DP, Büttner F, Huebschmann NA, Gardner AJ, Cook NE, Iverson GL. Systematic Review of Pre-injury Migraines as a Vulnerability Factor for Worse Outcome Following Sport-Related Concussion. Frontiers in Neurology. 2022. doi:10.3389/fneur.2022.915357
6. Patricios J, Schneider G, Ierssel JV, et al. Beyond acute concussion assessment to office management: a systematic review informing the development of a Sport Concussion Office Assessment Tool (SCOAT6) for adults and children. British Journal of Sports Medicine. 2023. doi:10.1136/bjsports-2023-106897
7. Hoppes CW, Huerta TGDL, Faull S, et al. Utility of the Vestibular/Ocular Motor Screening in Military Medicine: A Systematic Review.. Military medicine. 2025. doi:10.1093/milmed/usae494
