Aim: To know which is the best GCS score and FOUR score to be used in patients presenting    to Emergency Medicine department with altered mental status and also predicting the outcome   of patient.   Materials and Methods: This is a prospective observational comparative study. It included   100 patients of altered sensorium, whose GCS and FOUR scores were calculated at admission
and followed up till discharge or death to note the outcome. Individual demographics and   diagnosis were recorded, and the results were analyzed statistically.  Results: The ROC curve analysis for FOUR score in determining prognosis within 48 hours   of admission indicates moderate predictive power, with an area under the curve (AUC) of   0.632. The ROC curve analysis for GCS total demonstrated a stronger predictive power with  an AUC of 0.702. Conclusion: Both GCS and FOUR score can be used with same reliability in emergency to  predict outcome.Taking into account the possible inter observer variation FOUR score can be
used with upper hand.  Clinical significance: In critically-ill patients with altered sensorium, explaining the  prognosis to the attendants is a challenge for the physician. The commonly used GCS score has  several shortcomings, especially in intubated patients. Use of the FOUR score can overcome  these shortcomings and help in prognostication of these patients. In view of its good correlation  with GCS score and equal efficacy in predicting outcomes in varied etiologies, it can be used as
a good alternative to the GCS score.