Table 2.
Between-group differences and adjusted regression analyses
| Non-fallers (n = 58) | Fallers (n = 23) | Between-groupa | 25th – 75th quartiles | Regression adjusted for country, prior falls and assistance | Regression adjusted for country, prior falls, assistance and 6mWT | |||
|---|---|---|---|---|---|---|---|---|
| Mean ± SD | Mean ± SD | P-value | IQR-OR (95% CI) | P-value | IQR-OR (95% CI) | P-value | ||
| Gait variables | ||||||||
| 6mWT-comfortable, m/s (n = 57:23) | 0.78 ± 0.36 | 0.61 ± 0.32 | 0.075 | 0.45–0.98 | 2.10 (0.90–4.89)b | 0.086 | N/A | N/A |
| Kinect-fast walk, m/s (n = 56:23) | 0.93 ± 0.38 | 0.76 ± 0.37 | 0.106 | 0.57–1.16 | 1.89 (0.78–4.58)b | 0.157 | N/A | N/A |
| Stride length, m (n = 54:20) | 1.03 ± 0.26 | 0.87 ± 0.31 | 0.043* | 0.76-1.22 | 4.23 (1.14–15.66)b | 0.031* | 1.97 (0.26–14.79)b | 0.511 |
| Cadence, steps/min (n = 54:20) | 107.84 ± 23.50 | 95.48 ± 31.61 | 0.114 | 91.41–122.08 | 2.48 (0.96–6.41)b | 0.060 | 1.46 (0.45–4.81)b | 0.530 |
| Step width, m (n = 54:21) | 0.15 ± 0.04 | 0.15 ± 0.04 | 0.943 | 0.12–0.17 | 1.19 (0.56–2.52)b | 0.649 | 1.43 (0.65–3.13)b | 0.376 |
| Step length asymmetry, ratio (n = 53:20)c | 1.15 ± 0.16 | 1.54 ± 1.10 | 0.458 | 1.06–1.16 | 1.37 (1.01–1.85) | 0.040* | 1.28 (0.96–1.69) | 0.090 |
| Gait speed variability, m/s (n = 56:23)c | 0.17 ± 0.09 | 0.13 ± 0.04 | 0.048* | 0.11-0.18 | 1.82 (0.78–4.26)b | 0.169 | 1.24 (0.46–3.37)b | 0.670 |
| ML pelvic displacement, cm (n = 55:23) | 7.00 ± 1.26 | 5.24 ± 1.39 | < 0.001* | 5.38-7.22 | 7.85 (2.56–24.05)b | < 0.001* | 6.75 (2.20–20.74)b | 0.001* |
| Vertical pelvic displacement, cm (n = 55:23) | 3.42 ± 1.25 | 2.83 ± 0.96 | 0.047* | 2.26-4.10 | 2.03 (0.74–5.56)b | 0.168 | 1.25 (0.36–4.31)b | 0.724 |
| Balance variables | ||||||||
| TUG - normal, s (n = 58:23)c | 16.49 ± 9.26 | 27.61 ± 23.84 | 0.014* | 11.30-22.56 | 4.06 (1.44–11.46) | 0.008* | 7.84 (1.42–43.26) | 0.018* |
| TUG - dual task, s (n = 54:19)c | 21.47 ± 14.60 | 24.22 ± 3.06 | 0.148 | 11.91–25.44 | 1.30 (0.50–3.41) | 0.589 | 1.38 (0.35–5.39)b | 0.647 |
| Step test - affected, taps/15 s (n = 58:23) | 10.19 ± 5.08 | 6.35 ± 4.20 | 0.005* | 6.00-12.50 | 4.50 (1.64–12.35)b | 0.004* | 5.28 (1.46–19.16)b | 0.011* |
| Step test - less affected, taps/15 s (n = 58:23) | 8.95 ± 4.81 | 4.74 ± 3.44 | < 0.001* | 4.50-10.00 | 6.98 (2.06–23.61)b | 0.002* | 10.29 (2.26–46.84)b | 0.003* |
| COP vel EO total, cm/s (n = 57:22)c | 1.52 ± 0.65 | 1.96 ± 1.13 | 0.186 | 1.14–1.36 | 1.26 (0.61–2.61) | 0.527 | 1.29 (0.61–2.76) | 0.505 |
| COP vel EO ML, cm/s (n = 57:22)c | 0.68 ± 0.35 | 0.83 ± 0.50 | 0.193 | 0.43–0.86 | 1.40 (0.70–2.80) | 0.345 | 1.31 (0.64–2.69) | 0.458 |
| COP vel EO AP, cm/s (n = 57:22)c | 1.20 ± 0.55 | 1.59 ± 1.00 | 0.128 | 0.89–1.40 | 1.18 (0.64–2.17) | 0.590 | 1.24 (0.66–2.34) | 0.508 |
| COP vel EC total, cm/s (n = 56:22)c | 2.11 ± 0.94 | 2.75 ± 1.64 | 0.172 | 1.45–2.86 | 1.17 (0.49–2.78) | 0.725 | 1.20 (0.49–2.93) | 0.687 |
| COP vel EC ML, cm/s (n = 56:22)c | 0.79 ± 0.37 | 0.99 ± 0.53 | 0.127 | 0.52–1.10 | 1.63 (0.60–4.44) | 0.338 | 1.48 (0.53–4.14) | 0.461 |
| COP vel EC AP, cm/s (n = 56:22)c | 1.78 ± 0.84 | 2.35 ± 1.54 | 0.230 | 1.21–2.32 | 1.06 (0.49–2.32) | 0.882 | 1.12 (0.50–2.50) | 0.788 |
*Denotes a significance at P < 0.05
a Between-group differences assessed using Mann-Whitney U tests; b an inverse relationship with falls exists, therefore IQR-OR compares the odds of having more falls among individuals with predictor values at the 25th percentile with the odds of having more falls among individuals with predictor values at the 75th percentile; c log-transformed for regression analysis due to significant positive skew
Abbreviations, 6mWT 6-m walk test, AP anteroposterior, COP centre of pressure, EC eyes closed, EO eyes open, IQR interquartile range, ML mediolateral, OR odds ratio, TUG timed up and go