Table 2.
List of selected features comparing healthy to PwMS.
| No. | Feature | Raw P rank sum | Rank biserial | Healthy median ± MAD | PwMS median ± MAD | ICC |
|---|---|---|---|---|---|---|
| A | Total TUG duration thigh accel ant-post | 0.01606 | −0.453 | 9.14 ± 0.68 | 11.11 ± 2.27 | 0.86 |
| B | Total TUG duration stopwatch | 0.01183 | −0.473 | 10.27 ± 1.53 | 12.44 ± 2.70 | 0.86 |
| THIGH PITCH SIT-TO-STAND (ANGULAR VEL) | ||||||
| 1 | Thigh maximum arc B area under curve (abs) | 0.00003 | 0.785 | 11,720 ± 620 | 9,685 ± 1,292 | 0.69 |
| 2 | Thigh maximum arc D area under curve (abs) | 0.00004 | 0.775 | 11,634 ± 859 | 9,552 ± 1,309 | 0.62 |
| 3 | Thigh maximum arc F area under curve (abs) | 0.00005 | 0.760 | 11,448 ± 803 | 9,519 ± 1,244 | 0.61 |
| 4 | Thigh maximum sit-to-stand peak (abs) | 0.00030 | 0.678 | 117.91 ± 15.62 | 90.06 ± 15.07 | 0.74 |
| 5 | Thigh second step arc F mean (abs) | 0.00069 | 0.637 | 73.75 ± 9.22 | 55.12 ± 8.84 | 0.78 |
| 6 | Thigh maximum arc F mean (abs) | 0.00084 | 0.627 | 79.66 ± 9.59 | 63.44 ± 10.36 | 0.79 |
| 7 | Thigh minimum arc F mean (abs) | 0.00103 | 0.616 | 71.10 ± 11.27 | 55.12 ± 8.24 | 0.74 |
| 8 | Thigh first step sit-to-stand peak (abs) | 0.00103 | 0.616 | 110.09 ± 13.57 | 90.06 ± 15.07 | 0.59 |
| 9 | Thigh minimum arc D mean (abs) | 0.00165 | 0.591 | 69.85 ± 9.50 | 53.38 ± 7.57 | 0.71 |
| 10 | Thigh second step sit-to-stand peak (abs) | 0.00444 | 0.535 | 100.34 ± 14.66 | 86.35 ± 12.73 | 0.77 |
| THIGH PITCH STAND-TO-SIT (ANGULAR VEL) | ||||||
| 11 | Thigh maximum arc K area under curve (abs) | 0.00239 | 0.570 | 8,958 ± 1,026 | 7,137 ± 338 | 0.50 |
| 12 | Thigh maximum arc M area under curve (abs) | 0.00373 | 0.545 | 8,616 ± 686 | 6,931 ± 430 | 0.51 |
| 13 | Thigh minimum stand-to-sit peak (abs) | 0.09513 | 0.315 | 68.73 ± 7.40 | 60.01 ± 12.53 | 0.85 |
| SPINE PITCH (ANGULAR VEL) | ||||||
| 14 | Spine pitch sit-to-stand peak 2 (abs) | 0.00676 | 0.509 | 79.02 ± 11.37 | 60.92 ± 11.36 | 0.79 |
| 15 | Spine pitch sit-to-stand peak 1 (abs) | 0.00796 | 0.499 | 110.48 ± 14.30 | 83.21 ± 10.40 | 0.70 |
| 16 | Spine pitch stand-to-sit peak 1 (abs) | 0.07994 | −0.330 | 70.84 ± 8.66 | 62.65 ± 12.46 | 0.56 |
| 17 | Spine pitch arc Q AUC | 0.44364 | −0.146 | -3,355 ± 825 | −2,906 ± 914 | 0.66 |
| DURATIONS ALL | ||||||
| 18 | Thigh maximum arc F duration | 0.01858 | −0.442 | 1.19 ± 0.09 | 1.42 ± 0.15 | 0.62 |
| 19 | Thigh minimum arc D duration | 0.03871 | −0.389 | 0.81 ± 0.13 | 0.95 ± 0.16 | 0.78 |
| 20 | Spine sit-to-stand Weiss duration | 0.13923 | −0.279 | 0.70 ± 0.12 | 0.77 ± 0.19 | 0.67 |
| 21 | Spine stand-to-sit Weiss duration | 0.15867 | −0.266 | 1.01 ± 0.10 | 1.22 ± 0.32 | 0.54 |
| SPINE ROLL (ANGULAR VEL) | ||||||
| 22 | Spine roll arc D smoothness 2 | 0.00675 | 0.509 | −1.243 ± 0.100 | −1.413 ± 0.141 | 0.53 |
| 23 | Spine roll arc J mean (abs) | 0.06679 | −0.345 | 5.80 ± 1.84 | 8.69 ± 2.92 | 0.49 |
| 24 | Spine roll arc B mean (abs) | 0.07534 | −0.335 | 15.29 ± 3.69 | 21.34 ± 8.76 | 0.80 |
| 25 | Spine roll stand-to-sit peak 1 (abs) | 0.07534 | −0.335 | 30.75 ± 10.08 | 43.02 ± 15.07 | 0.75 |
| 26 | Spine roll stand-to-sit peak 2 (abs) | 0.11888 | −0.294 | 15.77 ± 6.53 | 21.09 ± 5.16 | 0.40 |
| 27 | Spine roll arc N smoothness 1 | 0.28596 | 0.202 | −0.0372 ± 0.0093 | −0.0423 ± 0.0172 | 0.09 |
All angular velocities refer to pitch unless stated as roll. The features in each category are listed in order of the effect size (rank biserial); note that some features (13, 16, 17, 22, 23–27) are included as illustrative rather than as discriminatory features. 819 features were tested, so that with a Holm-Bonferroni method for multiple comparisons, only features 1, 2, and 3 (Area Under the Curve for arcs B, D and F) are significant. Arcs are as listed in Figure 4.