Table 1.
Comparison of NASA-TLX and ICA at baseline and at a two-week follow-up (n = 38).
| Variable | Baseline | Follow-up | Pearson r | ICC, (95% CI) | MDC90 |
|---|---|---|---|---|---|
| 0-back, NASA-TLX | 19.51 (15.95) | 21.98 (17.89) | 0.68 a | 0.81 (0.61–0.90) a | 15.82 |
| 0-back, mean ICA L | 0.33 (0.14) | 0.24 (0.15) | 0.46 b | 0.63 (0.26–0.83) b | 0.20 |
| 0-back, mean ICA R | 0.27 (0.17) | 0.28 (0.16) | 0.55 b | 0.70 (0.40–0.85) a | 0.22 |
| 1-back, NASA-TLX | 28.24 (17.80) | 27.22 (16.96) | 0.60 a | 0.78 (0.57–0.89) a | 19.37 |
| 1-back, mean ICA L | 0.29 (0.17) | 0.27 (0.14) | 0.58 a | 0.73 (0.47–0.86) a | 0.20 |
| 1-back, mean ICA R | 0.25 (0.16) | 0.30 (0.15) | 0.39 c | 0.56 (0.12–0.78) b | 0.25 |
| 2-back, NASA-TLX | 50.92 (19.41) | 50.61 (19.13) | 0.55 b | 0.71 (0.42–0.85) a | 24.33 |
| 2-back, mean ICA L | 0.25 (0.14) | 0.23 (0.16) | 0.50 b | 0.64 (0.29–0.82) a | 0.24 |
| 2-back, mean ICA R | 0.24 (0.18) | 0.25 (0.15) | 0.45 b | 0.62 (0.20–0.82) b | 0.25 |
Abbreviations: CI, confidence interval; ICA, Index of Cognitive Activity; ICC, intraclass correlation coefficient; L, left, NASA-TLX, National Aeronautics and Space Administration Task Load Index; MDC, minimal detectable difference; R, right. a p < 0.0001, b p < 0.01, c p < 0.05.