Table 2.

Intra- and inter-observer variability of SDI measurement by 3DE

Study (reference)	Average value	Intra-observer variability (bias ± 2SD)	Inter-observer variability (bias ± 2SD)	n
Marsan et al. [24]	7.3	0.0 ± 0.5	0.1 ± 1.0	20
Kapetanakis et al. [38]	6.6	0.6 ± 4.9	0.5 ± 2.9	20
Marsan et al. [41]	8.4		0.1 ± 1.0	20
Van Dijk et al. [45]	8.9	0.0 ± 7.6	1.9 ± 5.0	20
Marsan et al. [46]	7.8	0.0 ± 0.4	0.1 ± 2.0	20
Delgado et al. [47]	7.9	0.0 ± 5.0	0.4 ± 6.4	18
Soliman et al. [50]	11.5	0.3 ± 3.4	0.3 ± 5.1	50