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Table 1 Spearman's rank correlation coefficients [95% confidence intervals] between the true full-shift exposure value M and the bias B, and between M and the sample standard deviation s y , for each of the seven sampling durations (5, 10, 20, 40, 60, 120, 240 min) and each of the four posture variables (10th, 50th, 90th percentiles, 10th-90th percentile range)
From: Bias and imprecision in posture percentile variables estimated from short exposure samples
| Posture variable: |
10th
percentile |
50th
percentile |
90th
percentile |
10th-90th
percentile range | |
|---|---|---|---|---|---|
| Mvs B | |||||
| Sampling duration, minutes | 5 |
0.64
[0.48;0.76] |
0.02 [-0.21;0.25] |
-0.65
[-0.76; -0.49] |
-0.66
[-0.77; -0.51] |
| 10 |
0.61
[0.45;0.74] |
0.03 [-0.20;0.26] |
-0.49
[-0.65; -0.29] |
-0.58
[-0.71; -0.40] | |
| 20 |
0.56
[0.38;0.70] |
0.08 [-0.15;0.31] |
-0.27
[-0.47; -0.04] |
-0.42
[-0.59; -0.21] | |
| 40 |
0.53
[0.34;0.68] |
0.30
[0.07;0.49] |
-0.17 [-0.38;0.06] |
-0.28
[-0.48;-0.06] | |
| 60 |
0.56
[0.38;0.70] |
0.28
[0.05;0.48] |
-0.10 [-0.32;0.14] |
-0.19 [-0.40;0.04] | |
| 120 |
0.57
[0.39;0.70] |
0.36
[0.15;0.55] |
-0.02 [-0.25;0.21] |
-0.07 [-0.29;0.17] | |
| 240 |
0.44
[0.23;0.61] |
0.43
[0.23;0.60] |
0.09 [-0.14;0.32] |
0.01 [-0.22;0.24] | |
| M vs s y | |||||
| Sampling duration, minutes | 5 |
0.70
[0.56;0.80] |
0.65
[0.50;0.77] |
0.77
[0.65;0.85] |
0.67
[0.52;0.78] |
| 10 |
0.70
[0.56;0.80] |
0.66
[0.51;0.77] |
0.73
[0.60;0.82] |
0.62
[0.46;0.75] | |
| 20 |
0.72
[0.58;0.81] |
0.59
[0.42;0.72] |
0.71
[0.57;0.81] |
0.60
[0.43;0.73] | |
| 40 |
0.68
[0.54;0.79] |
0.53
[0.34;0.68] |
0.72
[0.58;0.81] |
0.63
[0.46;0.75] | |
| 60 |
0.66
[0.51;0.77] |
0.52
[0.32;0.67] |
0.70
[0.57;0.80] |
0.63
[0.47;0.75] | |
| 120 |
0.64
[0.48;0.76] |
0.47
[0.27;0.63] |
0.67
[0.52;0.78] |
0.55
[0.37;0.70] | |
| 240 |
0.57
[0.39;0.71] |
0.40
[0.19;0.58] |
0.44
[0.23;0.61] |
0.36
[0.15;0.55] | |
