| Eye Opening (E) | Spontaneous | 4 |
| To sound | 3 | |
| To pressure | 2 | |
| None | 1 | |
| Not testable (NT) | — | |
| Verbal (V) | Oriented | 5 |
| Confused | 4 | |
| Inappropriate words | 3 | |
| Sounds only | 2 | |
| None | 1 | |
| Not testable (NT) | — | |
| Motor (M) | Obeys commands | 6 |
| Localizes | 5 | |
| Normal flexion | 4 | |
| Abnormal flexion | 3 | |
| Extension | 2 | |
| None | 1 | |
| Not testable (NT) | — |
| Mild TBI | 13 – 15 |
| Moderate TBI | 9 – 12 |
| Severe TBI | 3 – 8 |
| Trapezius | Grip 4–5 cm of muscle at neck–shoulder junction with thumb and two fingers | Clavicle or high spinal fracture |
| Supraorbital notch | Thumb pressure in supraorbital groove, ~2–3 cm from nasion | Orbital/facial/skull fracture; glaucoma |
| Retromandibular (TMJ) | Flat thumb pressure on both condyles at jaw angle | Mandibular fracture; raised ICP (may impair venous return) |
| Lateral digit | Barrel-of-pen pressure to outer aspect of distal index finger | Peripheral neuropathy (unreliable); not for lower limbs |
Apply noxious stimulus for no longer than 1–2 seconds. A nociceptive impulse reaches the brain in under 1 second. Observe for response for up to 30 seconds after releasing — do not prolong the stimulus itself. Minimise the number of applications: eye opening and motor response can be assessed simultaneously with a single stimulus.
| Obeys commands | M6 | Performs a two-part request (e.g. "Lift right arm and wiggle fingers") |
| Localizes | M5 | Hand crosses chin (to supra-orbital stimulus) or crosses midline (to nail-bed stimulus) |
| Normal flexion | M4 | Rapid elbow flexion, forearm supination, abduction — resembles withdrawal from heat |
| Abnormal flexion | M3 | Elbow flexion with adduction, internal shoulder rotation, wrist flexion (decorticate posturing) |
| Extension | M2 | Arm extension, internal shoulder rotation, supination of forearm (decerebrate posturing) |
| None | M1 | No movement to noxious stimulus, no interfering factor |
| ≤ 8 | Severe TBI — secure airway (intubation strongly indicated), urgent CT head, neurosurgical input, ICU admission |
| 9–12 | Moderate TBI — close monitoring, CT head, consider HDU/ICU depending on trajectory |
| 13–15 | Mild TBI — neuroimaging based on local criteria (e.g. NICE head injury rules), observe for deterioration |
Incorporate pupil reactivity to calculate GCS-P (GCS − PRS) in any patient with moderate-severe TBI. GCS-P provides superior mortality discrimination (AUC 0.77) versus GCS alone (AUC 0.69) and is particularly valuable for GCS 3 patients where it stratifies three markedly different mortality cohorts.
Teasdale G et al. • Lancet • 1974
Brennan PM et al. • J Neurosurg • 2018
Barea-Mendoza JA et al et al. • Emergencias • 2023
Cook N et al. • British Journal of Neuroscience Nursing • 2025
Reith FC et al. • Intensive Care Med • 2016
Moore L et al. • Journal of Trauma • 2006
The Glasgow Coma Scale was introduced in 1974 by neurosurgery professors Graham Teasdale and Bryan Jennett at the University of Glasgow. Originally published as a 14-point scale, it was revised in 1977 to 15 points by adding abnormal flexion to the motor component. A further revision was published in 2014, replacing "pain" with "pressure" as stimulus language and formalising the Not Testable (NT) category. Use became widespread in the 1980s after the first ATLS course endorsed it for all trauma patients. In 1988, the World Federation of Neurosurgical Societies adopted it for subarachnoid haemorrhage grading. The scale is now used in over 75 countries, incorporated into ICD-11, and referenced in over 37,000 publications with a 16.7% average annual citation growth rate since 1974.
| 1974 | Original 14-point GCS published — Teasdale & Jennett, Lancet |
| 1977 | Revised to 15 points — abnormal flexion added to motor component |
| 1980s | ATLS first edition endorses GCS for all trauma patients — widespread adoption begins |
| 1988 | WFNS incorporates GCS into subarachnoid haemorrhage grading scale |
| 2014 | GCS relaunched — "pressure" replaces "pain"; NT category formalised |
| 2018 | GCS-Pupils score (GCS-P) published — Brennan, Murray, Teasdale, J Neurosurg |
| 2023 | GCS-P externally validated in Spanish multicenter TBI registry (RETRAUCI, n = 1,551) |
| 2025 | International consensus standard for GCS education and practice published — BJNN |
Last Comprehensive Review: 2026
Last Comprehensive Review: 2026
