title: Predictive value of Glasgow Coma Scale after brain trauma: change in trend over the past ten years.
abstract: BACKGROUND
  Age and the Glasgow Coma Scale (GCS) score on admission are considered important predictors of outcome after traumatic brain injury. We investigated the predictive value of the GCS in a large group of patients whose computerised multimodal bedside monitoring data had been collected over the previous 10 years.
  
  
  METHODS
  Data from 358 subjects with head injury, collected between 1992 and 2001, were analysed retrospectively. Patients were grouped according to year of admission. Glasgow Outcome Scores (GOS) were determined at six months. Spearman's correlation coefficients between GCS and GOS scores were calculated for each year.
  
  
  RESULTS
  On average 34 (SD: 7) patients were monitored every year. We found a significant correlation between the GCS and GOS for the first five years (overall 1992-1996: r = 0.41; p<0.00001; n = 183) and consistent lack of correlations from 1997 onwards (overall 1997-2001: r = 0.091; p = 0.226; n = 175). In contrast, correlations between age and GOS were in both time periods significant and similar (r = -0.24 v r = -0.24; p<0.002).
  
  
  CONCLUSIONS
  The admission GCS lost its predictive value for outcome in this group of patients from 1997 onwards. The predictive value of the GCS should be carefully reconsidered when building prognostic models incorporating multimodality monitoring after head injury.
authors.affiliation: Academic Neurosurgical Unit, Addenbrooke's Hospital, Cambridge, UK.
authors.forename: M
authors.initials: M
authors.lastname: Balestreri
authors.forename: M
authors.initials: M
authors.lastname: Czosnyka
authors.forename: D A
authors.initials: DA
authors.lastname: Chatfield
authors.forename: L A
authors.initials: LA
authors.lastname: Steiner
authors.forename: E A
authors.initials: EA
authors.lastname: Schmidt
authors.forename: P
authors.initials: P
authors.lastname: Smielewski
authors.forename: B
authors.initials: B
authors.lastname: Matta
authors.forename: J D
authors.initials: JD
authors.lastname: Pickard
mesh_terms: D000293:Adolescent; D000328:Adult; D001930:Brain Injuries / Q000145:classification* / Q000473:pathology*; D015600:Glasgow Coma Scale / Q000639:trends*; D006801:Humans; D008875:Middle Aged; D019095:Point-of-Care Systems; D011237:Predictive Value of Tests; D011379:Prognosis; D012189:Retrospective Studies