2.6. Statistical analysis

Representative value was adopted from the average value for three trials and described as mean ± standard deviation. All statistical analysis were performed using JMP Pro version 15 (SAS Institute, Tokyo, Japan). The presence or absence of normality was confirmed by the Shapiro-Wilk test in all data sets. The demographic data, KAM peaks, MME_max, ΔMME, and gait parameters were compared between groups using the two sample t-test, and MME_min and FPA were analyzed using the Mann-Whitney Test. To compare between gait conditions in knee OA patients, the KAM peaks, MME_max, and ΔMME were analyzed using a paired t-test, and MME_min and FPA were analyzed using the Wilcoxon rank sum test. Moreover, a correlation between KAM and ΔMME in normal gait was performed by Pearson correlation analysis. On the other hand, the correlation between the difference in KAM and ΔMME was analyzed using Spearman's correlation analysis. The significance level was set at p < 0.05 in the statistical analysis. A post-hoc power analysis was performed using G∗power 3.1.9.2 software. In the comparison of ΔMME between conditions, the power was 0.95 with an effect size of 0.83.