How to Calculate a Patient’s Glasgow Coma Score

The Glasgow Coma Scale is a tool that has the ability to communicate the level of consciousness of patients with acute or traumatic brain injury.


Most commonly used in the ICU and ER, and only by trained medical professionals, the GCS is an objective and reliable tool that nurses and nursing students should become familiar with.


The Glasgow Coma Scale analyzes patients on three different criteria:


  • Eye opening
  • Motor response
  • Verbal response


Each criterion is on a different scale with a total possible score of 15, with 3 as the lowest possible score.




  • Closed by local factor -  (NT)
  • None - no opening at any time, no interfering factor (+1)
  • To Pressure - after fingertip stimulus (+2)
  • To Sound - after spoken request (+3)
  • Spontaneous - open before stimulus (+4)




  • Non-testable - factor interfering with communications (NT)
  • None - no audible response, no interfering factor (+1)
  • Sounds - only moan/groans (+2)
  • Words - intelligible single words (+3)
  • Confused - not oriented but communicates coherently (+4)
  • Oriented - correctly gives name, place, and date (+5)




  • Non-testable - paralyzed or other limiting factors (NT)
  • None - no movement in arms/legs, no interfering factor (+1)
  • Extension - extends arm  at elbow (+2)
  • Abnormal flexion - bends arm at elbow, features clearly predominantly abnormal (+3)
  • Normal flexion - bends arm at elbow rapidly but features not predominantly abnormal (+4)
  • Localising - brings hand above clavicle to stimulus on head/neck (+5)
  • Obeys command - 2-part request (+6)


The above scale is used by medical professionals for the best eye opening response, best motor response and best verbal response.


To calculate a patient’s GCS, first, score the patient on each of the three main areas. Once a number has been determined, add theses to create the sum which is the patient’s Glasgow score. It is better to understand the meaning once a score has been identified.


Though every brain injury is different, they are generally classified as:


  • Severe = GCS 3-8
  • Moderate = GCS 9-12
  • Mild = GCS 13-15


The GCS can be confusing but the first step in mastering it is to understand the basics.



 Published at: 11/22/2017