Test-Retest Reliability, Validity, and Minimal Detectable Change of the Balance Evaluation Systems Test to Assess Balance in Persons with Multiple Sclerosis

Abstract

Background: Individuals with multiple sclerosis (MS) have balance deficits that result in falls. Balance tests developed for older adults do not discriminate between fallers and nonfallers with MS. The Balance Evaluation Systems Test (BESTest) identifies body systems contributing to imbalance/fall risk. This study evaluated the test-retest reliability and construct validity of the BESTest to assess balance in individuals with MS, compared the diagnostic accuracy of the BESTest and Berg Balance Scale (BBS), and investigated the minimal detectable change of the BESTest in this population.

Methods: Twenty individuals with MS were recruited. Age, onset of disease, and fall history were obtained. The following measures were used: Expanded Disability Status Scale, University of Illinois at Chicago Fear of Falling Measure, BESTest, and BBS. Twelve participants were retested to determine test-retest reliability of the BESTest.

Results: The BESTest demonstrated strong test-retest reliability (intraclass correlation coefficient [3,1] = 0.98 [95% CI, 0.91-0.99], P = .01) and was highly correlated with the BBS (r = 0.94, P = .01). The BBS had poor accuracy to identify fallers. Using a score of 81%, the BESTest had moderate sensitivity (0.89) to identify fallers. The standard error of the measurement for the BESTest was 4.16 points, which translates into a minimal detectable change of 9.7% [90% CI] to 11.5% [95% CI].

Conclusions: The BESTest demonstrates excellent test-retest reliability and diagnostic utility as a measure of functional balance in persons with moderate MS. A change in BESTest score of at least 10% may indicate a true change in balance performance in this population.

Conflict of interest statement

The authors declare no conflicts of interest.

Figures

Figure 1.

Plot of Berg Balance Scale and Balance Evaluation Systems Test (BESTest) scores by participant Red dots indicate individuals who reported falling within past month.

Figure 2.

Receiver operating characteristic curve for Balance Evaluation Systems Test (BESTest) scores Star indicates BESTest cutoff score (81%) that seems to provide best balance between sensitivity and specificity for identifying fallers.