Fig. 1

Framework of the study. Left panel: The experimental set-up and the variables calculated from the CoP time-series data. Upper left pie chart shows the percentage of subjects in each clinical categorization. Right shows 23 variables used in the analysis and 17 variables rejected. Middle panel: Summary of the results obtained by the exploratory factor analysis (EFA). The color matrix shows the results of the factor loadings of each variable on the extracted factors. F1: magnitude of sway, F2: ML frequency component, F3: AP frequency component, F4: high-frequency component, F5: closed-loop control. Right panel: Comparison of factor scores by cluster in a Gaussian mixture model (GMM)-based cluster analysis. *p < 0.05, **p < 0.01 by post-hoc test (Steel–Dwass test) and Kruskal–Wallis test. Scatterplots shows the EFA in each cluster with 95% confidence ellipsoids and ellipses. Upper right pie chart: the percentage of each cluster