Association Between Physical Performance, Gait Variability, and Fall Risk in Community-Dwelling Older Adults: Predictive Validity of Step-Width Variability for Screening of Fall Risk

<b>Objective</b>: This cross-sectional study aimed to investigate the associations between physical performance, gait variability, and fall risk in community-dwelling older adults. <b>Methods</b>: A total of 446 participants were divided into fall-risk and non-fall-risk groups. Physical performance was assessed using hand grip strength (HGS), the Timed Up-and-Go (TUG) test, and the Five Times Sit-to-Stand test (5TSTS). Spatiotemporal gait parameters and their coefficients of variation (CV) were measured on a treadmill. <b>Results</b>: Logistic regression revealed that TUG, HGS, step-width CV, and velocity CV were significantly associated with fall risk, whereas age was not. Among these, TUG and step-width CV demonstrated the highest discriminative ability (AUC = 0.708 and 0.715, respectively). <b>Conclusions</b>: Step-width CV was a particularly sensitive indicator of gait stability. These findings suggest that a combination of TUG and step-width CV may help identify older adults at risk of falls, underscoring the importance of gait variability in fall risk screening.