Table 3.

Mean kidney volume differences applying a spheroid, an ellipsoid and a modified ellipsoid (result of the ellipsoid formula minus 15%) formula compared to manual segmentation

		N	Min.	5th percentile	Mean	95th percentile	Max.	SD	p value (two-tailed)
Spheroid volume VSp = π/6 × (L × D 2)	Reader 1	48	109.0	118.3	201.3	284.2	285.0	48.9	<0.01
	Reader 2	48	−26.9	−10.3	64.8	175.0	189.7	48.5	<0.01
	Reader 3	48	−89.7	−76.0	−11.0	71.8	92.5	39.7	0.06
	Total	144	−89.7	−48.4	85.0	257.6	285.0	99.2	<0.01
Ellipsoid volume VE = π/6 × (L × W × D)	Reader 1	48	−26.5	−17.9	19.9	66.7	70.7	22.1	<0.01
	Reader 2	48	−7.6	1.6	24.0	62.4	71.6	18.0	<0.01
	Reader 3	48	−13.3	−2.2	19.5	47.1	50.2	14.3	<0.01
	Total	144	−26.5	−7.0	21.2	55.9	71.6	18.4	<0.01
Modified ellipsoid volume VME = π/6 × (L × W × D) × 0.85	Reader 1	48	−37.3	−32.9	−1.1	38.8	43.7	18.7	0.67
	Reader 2	48	−29.8	−18.1	2.4	33.5	44.5	15.1	0.27
	Reader 3	48	−29.1	−19.6	−1.5	19.4	27.3	11.9	0.38
	Total	144	−37.3	−27.8	−0.1	23.9	44.5	15.5	0.95