Table 4. Qlab 7.0 and 8.1 Intra-observer reproducibility.
| Qlab 7.0 | Qlab 8.1 | ||||
| Endocardium | Epicardium | Endocardium | Epicardium | ||
| Repeat results | |||||
| Peak Twist (°) | (n = 15) | 1.3±3.4 (0.46) | 1.5±2.6 (0.33) | 0.9±0.07 (0.87) | −0.2±1.1 (0.90) |
| Peak Rotation (°) | Apex (n = 25) | 0.0±1.3 (0.96) | 0.3±1.7 (0.82) | −0.1±1.1 (0.97) | 0.1±0.8 (0.96) |
| Base (n = 25) | −0.2±1.2 (0.82) | 0.0±4.8 (0.68) | 0.1±0.9 (0.93) | 0.0±0.9 (0.87) | |
| tmax (s) | Apex (n = 25) | 0.00±0.02 (0.97) | 0.00±0.02 (0.96) | −0.0±0.04 (0.78) | 0.00±0.02 (0.92) |
| Base (n = 25) | 0.01±0.03 (0.86) | −0.01±0.05 (0.66) | −0.01±0.05 (0.70) | 0.01±0.06 (0.70) | |
| Long-term test-retest results | |||||
| Peak Twist (°) | (n = 20) | 3.67±3.96 (0.44) | 2.96±2.59 (0.38) | 0.48±1.66 (0.80) | −0.10±2.1 (0.54) |
| Peak Rotation (°) | Apex (n = 20) | −1.3±2.6 (0.32) | −1.6±2.1 (0.45) | 0.36±1.75 (0.63) | 0.03±1.9 (0.29) |
| Base (n = 20) | 2.4±3.2 (0.42) | 1.3±2.0 (0.23) | 0.11±1.45 (0.61) | 0.13±1.2 (0.55) | |
| tmax (s) | Apex (n = 20) | −0.01±0.06 (0.61) | −0.01±0.06 (0.53) | −0.02±0.07 (0.25) | −0.02±0.08 (0.22) |
| Base (n = 20) | 0.01±0.06 (0.55) | 0.02±0.07 (0.35) | −0.00±0.07 (0.51) | −0.01±0.06 (0.42) | |
| Peak transmural Torsion(°) | Apex (n = 25) | NA | −.022±0.9 (0.89) | ||
| Base (n = 25) | −0.35±1.4 (0.50) | ||||
| tmax (s) | Apex (n = 25) | 0.01±0.03 (0.89) | |||
| Base (n = 25) | 0.01±0.05(0.81) | ||||
Reproducibility of endocardial and epicardial peak twist, rotation and time to peak rotation measured at the left ventricle apex and the base. Data are average difference ±SDdiff (ICC, concordance correlation coefficient).