Glasgow Outcome Scale - Extended

Traumatic Brain Injury (Wilson, et al. 2000; n= 135; 36.74 (13.9) years (range 16-69 years old); admissions to regional neurosurgical unit with TBI, mean time post injury= 7.39 months (range 5-10 months post injury) ): assessed 5-10 months post injury and compared to the amount of time in PTA following injury. 

Brain Injury (Wilson, et al. 2002; n=141, mean age of 44.8 (19.1) years, administered either two postal surveys or phone vs. mail) 

Mean interval between completion of first questionnaire and second questionnaire = 14.4 (8.8) days; mean interval between phone and mail survey 6.4 (5.0 days). 

• Excellent test-retest reliability for postal surveys (weighted kappa coefficient = .98) 
• Excellent test-retest reliability for phone vs. mail survey (K=.92) 

Brain Injury: (Pettigrew, et al. 2003; n=30 ; mean age=36.77 (12.11) years old, (range from 19-68 years old); mean time post injury= 214 days (range from 168- 270 days) ) 

• Compared in-person versus telephone interview using the GOS-E 
• Excellent test-retest reliability (weighted kappa coefficient = .92)

Mild to Moderate TBI (Hong, 2016; (n = 89); Mean Age = 38.7 (16.0); mean 2.7 years post TBI (5.2); mild-moderate TBI)

• Excellent test-retest reliability: ( ICC = 0.92)

Brain Injury (participants from 32 trauma centers): (Lu, et al. 2010; tested three methods to improve agreement of ratings on 6 pre- and post-injury narratives completed by medical staff.) 

• Good to excellent interrater reliability (weighted kappa coefficient = .70-.95) improved by a method that encouraged the rating of the 5 level Glasgow Outcome Scale first, prior to determining GOS-E level, with central monitoring 

Brain Injury: (Mean age 39 (16) years, range 16-76) comparing psychologist and nurse, one in person and one by phone (Pettigrew, et al. 2003) 

• Excellent Interrater reliability (weighted kappa coefficient = .84-.92) 
• Minor Injury (weighted kappa coefficient = .89) and Severe Injury (weighted kappa coefficient = .92) 

Brain Injury : (Wilson, et al. 1998; n= 50; mean age = 39.4 (range 18-76 years old); post injury mean= 10.2 months(range 5-17 months post injury) ) 

• Excellent inter rater reliability (weighted kappa coefficient = .85)

Mild to Moderate TBI (Hong, 2016)

• Excellent interrater reliability: (Kappa =0.84) 
• Instrument demonstrated low person reliability (0.63)

Mild to Moderate TBI (Hong, 2016)

• Adequate Cronbach’s Alpha (a= 0.80)

Predictive Validity

Evaluating whether the GOS-E is a better predictor of Neuropsychological Outcome Measures than the GOS- 3 months post injury

Mild to moderate Traumatic Brain Injury: (Levin, et al., 2001; n= 43; mean age= 34.3 (14.1) years; evaluated at 1 month post injury and followed at 3 months post injury; n=44, mean age 36.9 years, patients with general trauma) 

• GOSE demonstrated stronger relationships with measures of functional outcome, affect and neuropsychological function, with greater sensitivity than GOS. However, scores for GOSE were not significantly different in the general trauma group than for those with mild to moderate TBI.

Brain Injury (ages 16-69): (Wilson, et al., 2000) 

• Excellent correlation with the DRS (r=-.89) and 
• Excellent correlation with the Beck Depression (r=-.64) 
• Adequate correlation with the length of PTA (r=-.52) and 
• Adequate correlation with the Barthel Index (r=.46) and 
• Adequate correlation with self-rated subscales of the NFI (r = ranges from .37-.63) 
• Adequate to excellent correlation with subscales of the SF-36 (r= ranges from .47-.71) 
• Adequate to excellent correlation with the subscales of the NFI-rated by relative/friend (r= ranges from .47-.69)

Construct Validity:

Moderate to Severe TBI (Dikmen et al., 2019; (n = 533); Mean Age = 36.25 (16.4); (mean 3,6 months post TBI; moderate-severe TBI)

• Spearman’s correlation is -0.88 at three months post-injury

Traumatic Brain Injury: (Hall, et al. 2001; n= 48; mean age= 37 years; mean time post injury= not documented, ranged from 2-9 years post injury) 

• Ceiling Effect: 69% for GOS, supporting the need for the more detailed GOS-E measure

Mild to Moderate TBI (Hong, 2016)

• authors interpretation: no quantitative information provided
  • Adequate slight ceiling effect (4.5%)
  • Excellent No floor effect

Moderate to Severe TBI (Dikmen et al., 2019)

• p^a < 0.001 paired Wilcoxon signed rank test comparing change from 3 to 6 months post-injury on the FSE.
• p^b < 0.001 paired Wilcoxon signed rank test comparing change from 3 to 6 months post-injury on the GOSE.
• p^c < 0.001 paired Wilcoxon signed rank test comparing whether there is more change on one measure compared with another.

Mean change 3-6 months post injury:

• FSE 1.97^a
• GOSE -0.42^b

Predictive validity:

Mild to severe non-penetrating TBI (Beer, 2012; (n = 159); (mean 80.9 months (56.9 months SD); 3 and 6 months after injury; mild to severe non-penetrating TBI)

• Excellent: GOS and VABS rs = - 0.687 ( p < 0.001);

Concurrent validity:

Mild to severe non-penetrating TBI (Beer, 2012, pg. 11)

• Excellent-Poor: See table

Correlation^a of GOS and GOS-E Peds at 3 Months with Outcome Measures at 6 Months

^aCorrelation by Spearman's rho (r_s).

^*p<0.001; ^†p<0.01; ^‡p<0.05.

GOS, Glasgow Outcome Scale; GOS-E Peds, Glasgow Outcome Scale-Extended Pediatric; CVLT-C, California Verbal Learning Test-Child; WISC-III, Wechsler Intelligence Scale for Children, 3rd Edition; SS, Standard Score; T, T score.

.

Discriminant validity:

Mild to severe non-penetrating TBI (Beer, 2012)

• Moderate-Weak: premorbid VABS Adaptive Behavior Composite r= .47; CPRS scores r= .001