Reliability, Validity, and Responsiveness of the Balance Evaluation Systems Test (BESTest) in Individuals with Multiple Sclerosis
Lisa Anderberg, SPT; Diana Anderson, SPT; Brooke Bauer, SPT; Megan Beste, SPT; Stephanie Navrat, SPT; Kirsten Potter, PT, DPT, MS

Purpose/Hypothesis: Individuals with Multiple Sclerosis (MS) demonstrate balance impairments for various reasons (such as, increased sway in quiet stance, delayed responses to perturbations, and reduced ability to move toward their limits of stability). This may indicate that they have impairments of various systems underlying postural control, which can be measured via the Balance Evaluation Systems Test (BESTest). Limited data exists to support the use of the BESTest in persons with MS. The purpose of this study was to determine the test-retest reliability, internal consistency, minimal detectable change (MDC), validity, and ceiling and floor effects of the BESTest in persons with MS. Subjects: Ambulatory subjects with MS Materials/Methods: Individuals with MS were recruited through the Mid America Chapter of the MS Society. In the first session, demographic data was collected, and each subject completed a disease severity (Expanded Disability Status Scale {EDSS} equivalent) questionnaire and the BESTest. One week later at the same time of day, subjects returned and the same examiner administered the BESTest. Results: 21 ambulatory subjects with MS (mean EDSS = 3.3; range 1-6) participated in this study. Test-retest reliability was excellent for the total BESTest score (ICC = 0.938) and good to excellent for subsection scores (range = 0.656 for Sensory Orientation to 0.933 for Dynamic Gait). Internal consistency for total BESTest was Chronbach’s alpha = 0.968; subsection scores ranged 0.792 for Sensory Orientation to 0.965 for Dynamic Gait. MDC scores ranged 2.25 – 2.62 points for Biomechanical, Stability Limits, Transitions/Anticipatory, and Sensory Orientation; 4.49 and 4.58 points for Reactive and Dynamic Gait, respectively; and 9.47 points for total BESTest. The relationships of individual subsection scores with each other were weak to moderate (Pearson coefficients range = -0.018 – 0.743). With the exception of the Stability Limits subsection, the relationship of BESTest total score to subsection scores was statistically significant with moderate to strong relationships (Pearson correlation coefficients range = 0.579 – 0.949). Correlations between BESTest total and subsection scores to EDSS, and to fall and loss of balance frequency, were weak to moderate. No significant floor effects were found. Ceiling effects were found for Biomechanical (38%), Stability Limits (29%), Reactive (24%), Sensory Orientation (62%), and Gait (24%). Conclusions: The BESTest is a reliable test in persons with MS. Weak to moderate correlations among individual subsection scores indicate that each assesses a unique underlying aspect of balance control, supporting its construct validity. ​The ceiling effect could be due to the relatively high functioning participants. Clinical Relevance: The BESTest is a reliable, valid, and responsive measure for use in ambulatory individuals with MS. Total BESTest scores demonstrated higher reliability and a lack of a ceiling effect as compared to subsection scores, suggesting that clinicians use the BESTest in its entirety.