Reproducibility and convergent validity of the blazepod stepping reaction test in older people

Introduction: Proper balance control requires adaptive stepping, a strategy frequently used to maintain balance at the critical moment of slipping or tripping. Previous studies have confirmed that a slow-stepping reaction is prevalent in older people. Furthermore, those with a slow-stepping reaction are at a higher risk of falling. Aim: Examine the convergent validity and intra-rater test-retest reproducibility of a novel instrumented stepping reaction test in older adults. Methods: The study was observational, encompassing a test-retest design. Main outcome measures included the novel instrumented Blazepod Stepping Reaction Test (BSRT), Mini-BESTest including subcategories (Anticipatory, Reactive Postural control, Sensory orientation, Dynamic gait), Timed Up and Go test (TUG), Choice Stepping Reaction Time test (CSRT), Fear of Falling (FoF), and Fall Status Questionnaire. Results: Fifty older people (33 women, 17 men), with a mean age of 72.2 (SD=4.2), were enrolled in the study. The mean BSRT test score of the study sample was 15.9 (SD=3.2). The intraclass correlation coefficient value for the intra-rater test-retest reproducibility of the BSRT test was 0.793 (95 %CI, 0.493, 0.912). The SEM and MDC values were 1.446 and 2.36, respectively. A moderate-strong correlation score was found between the BSRT and the TUG (r = -0.670). Moderate correlation scores were found between the BSRT and the Min-BESTest total score, anticipatory postural adjustment, and dynamic gait (r∼0.55). Moderate correlations were found between the BSRT, fear of falling (r = 0.40), the CSRT (r = -0.35), and balance sensory orientation (r = 0.37). No associations were found between the BSRT and reactive postural control. Conclusions: The current study supports the convergent validity and test-retest reproducibility of the BSRT in older people.