Table 3 Intra- and Inter-observer measurement variability for layer-specific two-dimensional speckle-tracking echocardiography
| Â | Intra-observer | Inter-observer | ||
|---|---|---|---|---|
SD | CV (%) | SD | CV (%) | |
 Longitudinal strain | ||||
  Whole layer | 0.67 | 4.3 | 0.85 | 5.6 |
  Endocardial layer | 0.76 | 3.9 | 1.04 | 6.0 |
  Epicardial layer | 0.73 | 5.8 | 0.74 | 5.8 |
  Endo/Epi | 0.04 | 3.1 | 0.02 | 5.8 |
 Circumferential strain | ||||
  Whole layer | 0.68 | 4.0 | 1.47 | 7.8 |
  Endocardial layer | 1.16 | 3.6 | 2.21 | 7.2 |
  Epicardial layer | 0.39 | 5.2 | 0.49 | 5.5 |
  Endo/Epi | 0.25 | 5.6 | 0.32 | 8.1 |