Table 5.
Standing on a compliant surface with eyes closed: values of individual variables for the first and second measurements, their absolute difference with intraclass correlation coefficients (ICC) with bottom and top limits of 95 % confidence intervals (CI)
| Age group | 1st measurement Average ± SD (SEM) |
2nd measurement Average ± SD (SEM) |
ICC | 95 % CI | |
|---|---|---|---|---|---|
| Medio-lateral variability (cm) | Young | 1.18 ± 0.18 (0.04) | 1.16 ± 0.20 (0.04) | 0.76 | 0.46–0.89 |
| Elderly | 1.51 ± 0.20 (0.06) | 1.46 ± 0.29 (0.08) | 0.80 | 0.33–0.94 | |
| Antero-posterior variability (cm) | Young | 1.33 ± 0.17 (0.03) | 1.21 ± 0.20 (0.04) | 0.67 | 0.14–0.87 |
| Elderly | 1.54 ± 0.24 (0.07) | 1.49 ± 0.19 (0.05) | 0.63 | −0.21–0.89 | |
| Medio-lateral path length (cm) | Young | 222.93 ± 56.79 (11.36) | 213.27 ± 55.57 (11.12) | 0.90 | 0.77–0.95 |
| Elderly | 328.61 ± 78.34 (21.73) | 314.43 ± 78.10 (21.66) | 0.88 | 0.60–0.96 | |
| Antero-posterior path length (cm) | Young | 231.83 ± 52.32 (10.46) | 213.51 ± 59.36 (11.87) | 0.88 | 0.69–0.95 |
| Elderly | 287.80 ± 61.11 (16.95) | 292.80 ± 58.35 (16.18) | 0.87 | 0.59–0.96 | |
| Total path length (cm) | Young | 357.76 ± 82.37 (16.47) | 335.63 ± 87.52 (17.50) | 0.90 | 0.76–0.96 |
| Elderly | 485.07 ± 102.25 (28.36) | 476.47 ± 104.15 (28.89) | 0.90 | 0.68–0.97 | |
| Mean velocity (cm/s) | Young | 5.97 ± 1.37 (0.28) | 5.60 ± 1.46 (0.29) | 0.90 | 0.76–0.96 |
| Elderly | 8.09 ± 1.71 (0.47) | 7.95 ± 1.74 (0.48) | 0.90 | 0.68–0.97 | |
| Sway area FAO (cm2) | Young | 31.45 ± 7.64 (1.53) | 30.18 ± 9.92 (1.98) | 0.83 | 0.62–0.92 |
| Elderly | 51.86 ± 15.08 (4.18) | 49.71 ± 14.61 (4.05) | 0.69 | −0.02–0.91 | |
| Sway area PCA (cm2) | Young | 19.14 ± 4.85 (0.97) | 17.17 ± 5.17 (1.03) | 0.83 | 0.57–0.93 |
| Elderly | 28.03 ± 6.77 (1.88) | 26.32 ± 7.03 (1.95) | 0.87 | 0.57–0.96 | |
| Fractal dimension ML short interval | Young | 1.11 ± 0.02 (0.00) | 1.11 ± 0.02 (0.00) | 0.78 | 0.50–0.90 |
| Elderly | 1.12 ± 0.03 (0.01) | 1.11 ± 0.02 (0.01) | 0.93 | 0.77–0.98 | |
| Fractal dimension ML long interval | Young | 1.98 ± 0.04 (0.01) | 1.97 ± 0.04 (0.01) | 0.68 | 0.29–0.86 |
| Elderly | 1.99 ± 0.03 (0.01) | 1.99 ± 0.02 (0.01) | 0.16 | −1.77–0.74 | |
| Fractal dimension AP short interval | Young | 1.15 ± 0.05 (0.01) | 1.14 ± 0.04 (0.01) | 0.86 | 0.70–0.94 |
| Elderly | 1.14 ± 0.03 (0.01) | 1.13 ± 0.03 (0.01) | 0.85 | 0.49–0.95 | |
| Fractal dimension AP long interval | Young | 1.98 ± 0.04 (0.01) | 1.98 ± 0.04 (0.01) | 0.65 | 0.22–0.84 |
| Elderly | 1.97 ± 0.04 (0.01) | 1.99 ± 0.03 (0.01) | 0.33 | −1.19–0.80 |
SD standard deviation, ML medio-lateral, AP antero-posterior, FAO Fourier analysis outline, PCA principal component analysis, short interval 0–0.3 s, long interval 0.8–12 s