Table 2.
Inter- and intra-observer reproducibility of PDFF
| Interobserver variability PDFF | Intra-observer variability PDFF | ||||||
| ICC (95% CI) | Difference (mean ± SD) | ICC (95% CI) | Difference (mean ± SD) | ||||
| Absolute (%) | Relative (%) | Absolute (%) | Relative (%) | ||||
| Psoas major muscle (right) | 0.94 (0.89;0.97) | −0.3 ± 0.9 | −3.7 ± 13.6 | 0.96 (0.93;0.98) | 0.1 ± 0.8 | 1.4 ± 12.0 | |
| Psoas major muscle (left) | 0.98 (0.97;0.99) | −0.2 ± 0.6 | −2.1 ± 9.3 | 0.98 (0.97;0.99) | −0.1 ± 0.5 | 0.2 ± 9.3 | |
| Quadratus lumborum muscle (right) | 0.97 (0.96;0.99) | 0.1 ± 0.7 | 2.6 ± 16.7 | 0.98 (0.96;0.99) | 0.1 ± 0.7 | 1.8 ± 14.7 | |
| Quadratus lumborum muscle (left) | 0.94 (0.9;0.97) | −0.1 ± 0.8 | 0.4 ± 17.6 | 0.98 (0.96;0.99) | 0.1 ± 0.5 | 1.4 ± 10.7 | |
| Autochthonous back muscles (right) | 0.98 (0.96;0.99) | −0.6 ± 1.5 | −3.4 ± 10.9 | 0.99 (0.98;0.99) | −0.2 ± 1.2 | −1.1 ± 7.2 | |
| Autochthonous back muscles (left) | 0.99 (0.98;0.99) | −0.3 ± 1.3 | −2.4 ± 8.7 | 0.99 (0.99;1.0) | 0.3 ± 1.0 | 1.9 ± 7.1 | |
| Rectus abdominis muscle (right) | 1.0 (0.99;1.0) | −0.4 ± 1.4 | −5.9 ± 17.3 | 1.0 (0.99;1.0) | 0.1 ± 1.5 | −1.3 ± 10.8 | |
| Rectus abdominis muscle (left) | 0.99 (0.98;0.99) | −0.2 ± 1.4 | −2.8 ± 14.4 | 0.99 (0.97;0.99) | −0.2 ± 1.5 | −0.1 ± 13.2 | |
| Mean skeletal muscle (bilaterally) | 0.99 (0.98;1.0) | −0.2 ± 0.5 | −2.6 ± 6.4 | 1.0 (0.99;1.0) | 0.0 ± 0.4 | 0.4 ± 3.8 | |
CI, confidence interval; ICC, intraclass correlation coefficient; PDFF, proton-density fat fraction.