Table 2.
Intra-rater reliability of the phone (n = 16)
| Phone D1 (Mean ± SD) | Phone D2 (Mean ± SD) | ICC (3,3) | 95% CI | Sys bias | Width of 95% LoA | % Error † | Prop bias € | Fixed bias € | SEM | MDC | LOA 2SD (mean diff ±2.1*SDdiff) | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Flexion |
51.3 ± 7.9 |
54.9 ± 7.5 |
0.86 |
0.38-0.96 |
N |
9.1 |
9 |
N |
N |
3.1 |
9.2 |
-12.84 to 5.48 |
| Extension¥ |
79.0 ± 7.6 |
80.8 ± 7.03 |
0.82 |
0.49-0.94 |
N |
11.8 |
7 |
N |
N |
5.0 |
11.9 |
-13.67 to 10.3 |
| Right Lateral Flexion |
43.5 ± 6.7 |
44.9 ± 7.0 |
0.90 |
0.73-0.97 |
N |
8.3 |
9 |
N |
N |
2.8 |
8.3 |
-9.73 to 6.95 |
| Left Lateral Flexion |
49.1 ± 8.8 |
51.2 ± 7.4 |
0.85 |
0.57-0.95 |
N |
11.8 |
12 |
N |
N |
4.1 |
12.2 |
-14.20 to 10.16 |
| Right Rotation |
50.0 ± 17.1 |
70.5 ± 22.7 |
0.33 |
-0.34-0.73 |
N |
48.2 |
40 |
N |
N |
16.4 |
48.7 |
-70.79 to 29.81 |
| Left Rotation | 64.3 ± 16.3 | 69.8 ± 15.6 | 0.05 | -1.7-0.67 | N | 46.8 | 35 | N | N | 15.8 | 46.9 | -52.38 to 41.36 |
SD = standard deviation; ICC = intra-class coefficients; CI = confidence interval; Sys Bias = systematic bias; LoA = limits of agreement; Prop Bias = proportional bias; N = no; Y = yes; SEM = standard error of measurement; MDC = minimal detectable change; diff = difference.
¥Based on n = 15 as one subject’s thoracic spine was not well stabilized.
†% Error = 0.5*Width of 95% LOA/[(MeanPhone + MeanVicon)/2].
€Proportional and fixed bias were determined from ordinary least products analysis.