Table 4.

Inter- and intra-observer reproducibility for 8 randomly chosen cases (4 PAH, 4 normal controls).

Variables	Variability	Mean bias±SD	Limits of agreement	CV (%)	ICC (95% CI)
${\epsilon }_{CC}^{RV}$	Intra-observer	0.5 ± 0.9	−1.3 to 2.4	8.1	0.91 (0.55, 0.98)
	Inter-observer	0.9 ± 0.7	−0.5 to 2.3	8.5	0.96 (0.80, 0.99)
${\epsilon }_{CC}^{LV}$	Intra-observer	0.0 ± 1.2	−2.3 to 2.3	5.9	0.92 (0.60, 0.98)
	Inter-observer	1.3 ± 0.9	−0.5 to 3.2	8.0	0.96 (0.81, 0.99)
${\epsilon }_{CC}^{Sep}$	Intra-observer	0.2 ± 0.9	−2.0 to 1.6	11.4	0.94 (0.81, 0.99)
	Inter-observer	0.5 ± 0.9	−1.3 to 2.3	12.7	0.94 (0.72, 0.99)
${\epsilon }_{LL}^{RV}$	Intra-observer	0.1 ± 1.3	−2.4 to 2.6	6.4	0.97 (0.93, 0.99)
	Inter-observer	−0.9 ± 0.9	−2.7 to 1.0	7.0	0.98 (0.90, 1.00)
${\epsilon }_{LL}^{LV}$	Intra-observer	−0.2 ± 1.4	−2.9 to 2.5	6.1	0.95 (0.75, 0.99)
	Inter-observer	1.6 ± 1.3	−0.9 to 4.2	6.8	0.89 (0.44, 0.98)
${\epsilon }_{LL}^{Sep}$	Intra-observer	−0.1 ± 1.5	−3.2 to 2.9	6.7	0.95 (0.77, 0.99)
	Inter-observer	−0.6 ± 1.6	−3.6 to 2.5	7.5	0.94 (0.71, 0.99)
${\epsilon }_{RR}^{RV}$	Intra-observer	−1.0 ± 2.9	−6.7 to 4.6	8.7	0.98 (0.92, 1.00)
	Inter-observer	−0.6 ± 2.2	−3.7 to 4.9	7.1	0.99 (0.93, 1.00)
${\epsilon }_{RR}^{LV}$	Intra-observer	−0.8 ± 5.0	−10.6 to 9.0	10.7	0.97 (0.84, 0.99)
	Inter-observer	−2.3 ± 6.0	−14.0 to 9.4	14.5	0.84 (0.21, 0.97)
${\epsilon }_{RR}^{Sep}$	Intra-observer	0.7 ± 1.9	−2.9 to 4.4	10.4	0.98 (0.89, 1.00)
	Inter-observer	−0.6 ± 1.4	−3.3 to 2.2	8.5	0.98 (0.92, 1.00)

${\mathit{\epsilon }}_{\mathit{C}\mathit{C}}^{\mathit{R}\mathit{V}}$: right ventricular peak circumferential strain; ${\mathit{\epsilon }}_{\mathit{C}\mathit{C}}^{\mathit{L}\mathit{V}}$: left ventricular peak circumferential strain; ${\mathit{\epsilon }}_{\mathit{C}\mathit{C}}^{\mathit{S}\mathit{e}\mathit{p}}$: septum peak circumferential strain. ${\mathit{\epsilon }}_{\mathit{L}\mathit{L}}^{\mathit{R}\mathit{V}}$: right ventricular peak longitudinal strain; ${\mathit{\epsilon }}_{\mathit{L}\mathit{L}}^{\mathit{L}\mathit{V}}$: left ventricular peak longitudinal strain; ${\mathit{\epsilon }}_{\mathit{L}\mathit{L}}^{\mathit{S}\mathit{e}\mathit{p}}$: septum peak longitudinal strain; ${\mathit{\epsilon }}_{\mathit{R}\mathit{R}}^{\mathit{R}\mathit{V}}$: right ventricular peak radial strain; ${\mathit{\epsilon }}_{\mathit{R}\mathit{R}}^{\mathit{L}\mathit{V}}$: left ventricular peak radial strain; ${\mathit{\epsilon }}_{\mathit{R}\mathit{R}}^{\mathit{S}\mathit{e}\mathit{p}}$: septum peak radial strain; SD: standard deviation; CV: coefficient of variation; ICC: intra-class correlation coefficient; CI: confidence interval.