Table 3.

Log-transformed backscatter coefficient inter-platform reproducibility for measurements based on a single acquisition (N=1) and on the mean of multiple repeated intra-platform acquisitions (N=2, 3, 4, and 5).

Number of acquisitions N	GE mean ± SD (dB)	Siemens mean ± SD (dB)	ICC (95% CI)
1	−30.8 ± 4.9	−27.8 ± 5.7	0.67 (0.19, 0.85)
2	−30.7 ± 4.9	−27.7 ± 5.7	0.68 (0.23, 0.85)
3	−30.7 ± 5.0	−27.8 ± 5.7	0.69 (0.24, 0.85)
4	−30.6 ± 5.0	−27.8 ± 5.7	0.70 (0.26, 0.86)
5	−30.6 ± 5.0	−27.9 ± 5.6	0.70 (0.28, 0.86)

ICC was calculated based on a single-unit, absolute-agreement, two-way mixed effect analysis of variance (ANOVA) model.

CI confidence interval, ICC intraclass correlation coefficient, SD standard deviation