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. 2017 Oct 10;17(10):2301. doi: 10.3390/s17102301

Table 1.

Mean values, between-subjects standard deviations (SD), agreement statistics (bias, limits of agreement [95% LoA] and intraclass correlation coefficients for absolute agreement [ICC(A,1)] and consistency [ICC(C,1)]) and results of the two one-sided t-tests (TOST) for the foot placement locations, step lengths and stepping accuracies for all combinations of the independent variables Distance (2 m, 3 m), Side (left, right) and Imposed Step Length (50 cm, 60 cm, 70 cm, 80 cm, 90 cm).

Kinect v2 Optotrak TOST
Mean ± SD Mean ± SD Bias [95% LoA] ICC(A,1) ICC(C,1) p-Value
Foot placement location (cm) 2 m Left 50 cm −0.02 ± 0.87 −0.48 ± 1.33 0.46 [−1.93 2.85] 0.403 0.413 <0.001
60 cm −0.04 ± 1.24 −0.51 ± 1.67 0.47 [−2.06 3.00] 0.608 0.615 <0.001
70 cm 0.02 ± 0.84 −0.61 ± 1.30 0.62 [−2.10 3.35] 0.178 0.193 0.004
80 cm 0.47 ± 0.96 −0.29 ± 1.10 0.76 [−1.84 3.36] 0.147 0.174 0.005
90 cm 0.01 ± 1.06 −0.73 ± 1.03 0.75 [−1.95 3.45] 0.115 0.135 0.005
Right 50 cm 0.34 ± 1.35 −0.95 ± 1.03 1.28 * [−0.46 3.03] 0.471 0.727 0.007
60 cm 0.68 ± 1.77 −0.77 ± 1.18 1.45 * [−0.79 3.70] 0.493 0.709 0.045
70 cm 1.32 ± 1.17 −0.22 ± 0.79 1.54 * [−0.33 3.41] 0.254 0.544 0.038
80 cm 0.57 ± 1.21 −1.04 ± 0.68 1.61 * [−0.48 3.69] 0.182 0.414 0.072 **
90 cm 0.65 ± 1.52 −0.94 ± 1.04 1.59* [−1.02 4.20] 0.282 0.478 0.110 **
3 m Left 50 cm −0.22 ± 1.16 −0.80 ± 1.13 0.58 [−1.69 2.85] 0.458 0.493 0.001
60 cm −0.10 ± 1.09 −0.44 ± 1.30 0.34 [−2.38 3.07] 0.334 0.325 0.001
70 cm −0.55 ± 1.57 −1.25 ± 1.50 0.70 [−2.89 4.29] 0.275 0.284 0.017
80 cm −0.00 ± 1.96 −0.79 ± 1.91 0.79 [−3.02 4.60] 0.480 0.495 0.027
90 cm −0.62 ± 1.51 −1.07 ± 1.82 0.45 [−2.92 3.83] 0.477 0.469 0.006
Right 50 cm −0.49 ± 1.48 −0.63 ± 1.64 0.14 [−2.84 3.11] 0.550 0.526 0.001
60 cm 0.28 ± 1.59 0.02 ± 1.85 0.26 [−1.71 2.22] 0.836 0.831 <0.001
70 cm 0.54 ± 1.34 0.04 ± 1.62 0.51 [−1.47 2.48] 0.744 0.770 <0.001
80 cm 0.25 ± 1.42 −0.00 ± 2.13 0.25 [−2.39 2.89] 0.736 0.723 <0.001
90 cm 0.04 ± 1.32 −0.57 ± 1.33 0.61 [−1.13 2.35] 0.717 0.777 <0.001
Step length (cm) 2 m Left 50 cm 49.19 ± 1.38 50.32 ± 1.46 −1.13 * [−3.05 0.80] 0.590 0.761 0.005
60 cm 59.32 ± 1.41 60.46 ± 1.50 −1.14 * [−3.36 1.08] 0.546 0.696 0.010
70 cm 69.09 ± 0.94 70.20 ± 1.27 −1.12 * [−3.18 0.95] 0.380 0.554 0.006
80 cm 79.45 ± 1.09 80.13 ± 1.40 −0.68 [−3.04 1.67] 0.492 0.542 0.002
90 cm 90.06 ± 0.98 91.25 ± 1.38 −1.19 * [−3.95 1.58] 0.213 0.304 0.030
Right 50 cm 49.02 ± 1.73 51.33 ± 1.37 −2.31 * [−3.59 −1.03] 0.439 0.913 0.773 **
60 cm 58.73 ± 1.44 61.05 ± 1.30 −2.32 * [−3.77 −0.87] 0.353 0.854 0.762 **
70 cm 67.50 ± 1.66 69.98 ± 1.39 −2.49 * [−4.64 −0.33] 0.325 0.744 0.825 **
80 cm 79.52 ± 1.03 81.17 ± 1.25 −1.65 * [−2.97 −0.32] 0.411 0.827 0.022
90 cm 89.49 ± 1.61 91.24 ± 1.72 −1.75 * [−3.41 −0.10] 0.566 0.871 0.089 **
3 m Left 50 cm 50.66 ± 1.35 50.73 ± 1.16 −0.06 [−1.92 1.80] 0.737 0.717 <0.001
60 cm 60.18 ± 1.50 60.28 ± 1.38 −0.10 [−2.69 2.49] 0.605 0.581 <0.001
70 cm 69.92 ± 1.91 70.78 ± 1.82 −0.85 [−5.72 4.02] 0.110 0.112 0.067 **
80 cm 78.81 ± 2.14 80.02 ± 1.78 −1.21 [−5.81 3.38] 0.258 0.289 0.120 **
90 cm 89.64 ± 1.99 90.74 ± 1.78 −1.11 [−5.60 3.38] 0.242 0.266 0.093 **
Right 50 cm 50.79 ± 2.00 50.41 ± 2.10 0.39 [−2.77 3.55] 0.699 0.690 0.004
60 cm 59.53 ± 1.97 59.65 ± 2.15 −0.12 [−2.60 2.36] 0.826 0.812 <0.001
70 cm 69.60 ± 1.22 69.59 ± 1.54 0.01 [−2.61 2.62] 0.568 0.542 <0.001
80 cm 79.44 ± 1.43 79.43 ± 2.29 0.00 [−3.52 3.53] 0.582 0.556 0.002
90 cm 89.69 ± 1.32 89.63 ± 1.78 0.06 [−2.72 2.84] 0.615 0.590 <0.001
Stepping accuracy (cm) 2 m Left 1.33 ± 0.29 1.28 ± 0.33 0.05 [−0.24 0.33] 0.892 0.892 <0.001
Right 1.30 ± 0.30 1.21 ± 0.26 0.08 [−0.18 0.35] 0.855 0.884 <0.001
3 m Left 1.52 ± 0.54 1.57 ± 0.61 −0.05 [−0.51 0.41] 0.922 0.917 <0.001
Right 1.43 ± 0.47 1.48 ± 0.54 −0.05 [−0.78 0.68] 0.745 0.729 <0.001

* Significant between-systems difference (p < 0.05); ** Non-significant two one-sided t-tests, indicating nonequivalence (TOST p > 0.05).