Table 1.

Accuracy of angular phantom measurements.

Phantom Position	Measurement category	Mean difference (True value − MRI)	95% limits of agreement (True value − MRI)	p-value
1	3D angles (°)	0.04	−0.20, 0.29	<0.001
	2D angles sagittal (°)	0.01	−0.36, 0.38	<0.001
	2D angles frontal (°)	0.03	−0.25, 0.31	<0.001
	2D angles horizontal (°)	−0.09	−0.98, 0.76	<0.001
2	3D angles (°)	0.00	−0.27, 0.26	<0.001
	2D angles sagittal (°)	0.04	−0.35, 0.43	<0.001
	2D angles frontal (°)	0.01	−0.26, 0.28	<0.001
	2D angles horizontal (°)	0.03	−0.35, 0.41	<0.001
3	3D angles (°)	0.01	−0.19, 0.20	<0.001
	2D angles sagittal (°)	−0.02	−0.31, 0.27	<0.001
	2D angles frontal (°)	−0.03	−0.20, 0.14	<0.001
	2D angles horizontal (°)	−0.07	−0.47, 0.33	<0.001

All given values refer to 24 different angles per measurement category. p-values < 0.05 indicate equivalence between true values and MRI measurements (two one-sided tests with an equivalence margin of ±0.5°).