Neurocritical Care

, Volume 14, Issue 1, pp 134–143 | Cite as

Evaluation of Coma: A Critical Appraisal of Popular Scoring Systems



Numerous scoring scales have been proposed and validated to evaluate coma for rapid pre-hospital assessment and triage, disease severity, and prognosis for morbidity and mortality. These scoring systems have been predicated on core features that serve as a basis for this review and include ease of use, inter-rater reliability, reproducibility, and predictive value. Here we review the benefits and limitations of the most popular coma scoring systems. The methods include search of Medline, databases, and manual review of article bibliographies. Few of the many available coma scales have gained widespread approval and popularity. The best known and widely accepted scale is the Glasgow Coma Scale (GCS). The Reaction Level Scale (RLS85) has utility and proven benefit, but little acceptance outside of Scandinavia. The newer Full Outline of UnResponsiveness (FOUR) score provides an attractive replacement for all patients with fluctuating levels of consciousness and is gradually gaining wide acceptance.


Coma GCS FOUR score RLS85 Consciousness 


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© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  1. 1.Department of NeurologyTufts University School of MedicineBostonUSA

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