Sensory Organization Test

Wrisley et al 2007 (n = 13 healthy young adults (mean age 24±4 years, 6 men) tested 2 days apart)

• Composite Score: SEM (calculated) = 2.81

Wrisley et al 2007: a composite change of greater than 8 points  would indicate a change due to rehabilitation (n = repeated testing of 13 healthy young adults)

Whitney et al 2006 : SOT composite score of less than 38 increases the likelihood ratio (4.13) for identifying repeated fallers in the past 6 months (n =100 vestibulopathic individuals) (sensitivity 53%, specificity 87%)

The SOT composite score and condition 2-6 significantly decreases with increased age in healthy individuals: ANOVA on SOT equilibrium score showed a main effect of age F(3.90) = 23.24 and  test condition (F(5.90) = 355.91.

Ford-Smith et al 1995 : Healthy non-institutionalized older adults (n = 40): Tested at a one week interval: Composite score: Good test-retest reliability (ICC 0.66, SOT average of three trials ranged from poor (Condition 3: ICC = 0.68) to fair test-retest reliability (condition 5: ICC = 0.68, condition 6: ICC = 0.64) 

Wrisley et al 2007

• Adequate composite score reliability ICC = 0.67
• Individual equilibrium scores ranged from poor to adequate ICC = 0.35 -0.79

Cohen et al 2008: SOT vestibular condition (condition 5/1) had moderately high sensitivity (85%) and specificity (77%) in identifying vestibulopathies (n = 40 adults, 40 adults with vestibular impairements) 

The review article by Di Fabio (1995) reports that many studies on sensitivity and specificity of using the SOT to identify people with vestibulopathy,  most studies found  low to moderate sensitivity and specificity. The responsiveness increases when the SOT is combined with rotary chair or caloric test results.  

Basta et al 2005 investigated the influence of pure otolith disorders on SOT scores in 33 adults with minor head injury with utrical or sacculo-utricalar disorders, finding SOT were abnormal in 76.9% of the people with combined sacular-utricular involvement, while the scores were only abnormal in 45% of utricular disorder group.

Gill-Body et al 2000: SOT, Timed up and Go(TUG), Dizziness Handicap Inventory (DHI) scores of people with unilateral (n = 41) and bilateral (n = 44) vestibular hypofunction: bilateral vestibular hypofunction: Adequate correlation (-0.31) between DHI emotional score and  mean SOT sway in condition 3, and in unilateral vestibular hypofunction clients an adequate correlation (-0.35) was found between mean sway in condition 3 and the physical DHI score

TUG scores were not correlated to any SOT scores for both groups 

Whitney et al 2006: The composite score and self-reported falls history within the past 6 months were significantly related (F3 5.81, p < 0.01) (n = 100 vestibulopathic individuals)

(Whitney and Wrisley, 2004; n = 30; mean age = 63 (17); patients with balance and vestibular disorders, Balance and Vestibular Disorders)

• Modified CTSIB and SOT (Sensory Organization Test) scores were slightly more correlated when participants completed the assessment with their feet together than when completed with feet apart.

Basta et al 2007: Sensitivity and Specificity of the SOT to detect otolith disorders (as measured by VEMP and Subjective Visual Vertical tests (n = 22 patients and controls): Sensitivity = solely in condition 3,5 and 6 is it higher than 50%)              

Specificity = decreases with increasing difficulty of the condition

(Landers MR et al, 2008) 

• SOT was not found to be a sensitive means of differentiating fallers from non-fallers; AUC – 62.6 with cut off score of 68.5; sensitivity = .60, specificity = .625, +LR = 1.60, -LR = .64, odds ratio = 2.5 (0.80 -7.9) 

(Rossi et al, 2009; n = 45 with PD (26 men, 19 women); mean age = 70.4 years (range = 46-82 years); Average time since diagnosis = 4.53 (2.9) years; H&Y I = 0; H&Y II = 17; H&Y III = 20; H&Y IV = 8. Controls were 20 healthy volunteers mean age 68.7 (range 60-84) years; 10 men, 10 women) 

• Individuals with PD performed significantly worse on the SOT than controls; condition 3 (p = 0.022), condition 4 (p = 0.014), condition 5 (p = 0.002), condition 6 (p = 0.002). Sensory Analysis individuals with PD had significantly worse performance on average balance (p = 0.001), visual input (p = 0.014), and vestibular input (p = 0.002). 

• Pathological balance scores (<68) were found in 24 of 45 individuals (6 in H&Y II, 12 in H&Y III, 6 in H&Y IV). 

(Franklach et al, 2009; 102 subjects with PD (25 women, 77 men), mean age 60.2 (9.3) years; There was a subgroup of 18 individuals who had UPDRS III score < 20 and never had medication and 25 control subjects (18 women, 7 men) mean age 56.9 (8.4) years. 

• No statistical difference between PD patients with UPDRS < 20 and controls on any SOT condition 

• PD patients with UPDRS III scores > 20 and controls differed significantly (p < 0.01) in all 6 SOT conditions 

• The equilibrium score for each SOT condition correlated with the UPDRS III score; Spearman rank correlation, SOT 1, 4, 5 (p < 0.0001); SOT 2 (p < 0.02); SOT 3, 6 (p < 0.001). 

(Colnat-Coulbois et al 2011, 24 subjects in late stage PD (10 women, 14 men), mean age 60.0 (14) years. 48 control subjects (20 women, 28 men), mean age 62.0 (11.0) years. Median disease duration for the PD group was 11 years, all were in H&Y stage IV) 

• Individuals in late stage PD had significantly lower scores on SOT indicating poorer equilibrium (z = -5.93, p < 0.001) and lower strategy scores (z = -3.67, p < 0.001) than healthy controls 

• The PD group had more difficulty controlling balance sways in more complex sensory conflict situations: in which visual information is the main reliable cue (z = -2.98, p = 0.003); vestibular information was the main reliable cue (z = -4.80, p < 0.001); proprioceptive information is disrupted (z = -4.77, p < 0.001). 

(Chong R et al. 1999, 15 individuals with PD (8 females, 7 males), mean age 60 (9) years. 11 subjects with Alzheimers disease (5 females, 6 males), mean age 73 (10) years. 17 healthy controls (8 females, 9 males), mean age 65 (6) years.) 

• Individuals with PD had more falls during the SOT than the control group x2(1) = 6.4, p < 0.05) but were equivalent to those with Alzheimers. 

• In condition 6 in which both visual and proprioceptive information is incongruent 53% of the PD subjects fell in the first trial, 100% of AD subjects lost their balance and 59% of the healthy controls. Both healthy controls and PD subjects improved performance in trials 2 and 3 while subjects with AD did not improve. 

(Lee JM et al. 2012, 31 individuals with early stage PD (H&Y 1 to 2.5), (16 women, 15 men) mean age 68.1 (7.28) years; 20 healthy control subjects (10 women, 10 men) mean age 66.6 (7.8) years. 

• No difference in equilibrium control between early stage PD and control subjects.

a= Kruskal-Wallis test

Parkinson Disease: 

(Colnat-Coulbois et al. 2011) 

• 24 individuals in H&Y stage IV were able to successfully complete the test indicating no floor effect for ambulatory individuals with PD.