Table 2. Comparison of signal, noise, SNR and CNR between the reconstructions FBP/QDS, AIDR 3D mild, AIDR 3D standard and AIDR 3D strong.

									ANOVA	t-test
	FBP/QDS		MILD		STD		STR		p	p1	p2	p3	p4	p5	p6
Signal	155.3	(53.7)	155.0	(53.5)	152.5	(53.4)	149.9	(53.3)	<0.001	1.000	<0.001	<0.001	<0.001	<0.001	<0.001
Noise	32.8	(9.3)	34.5	(8.9)	29.8	(8.3)	27.0	(7.8)	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001
SNR	10.4	(3.0)	9.4	(3.0)	11.1	(3.7)	12.6	(4.4)	<0.001	0.001	0.001	<0.001	<0.001	<0.001	<0.001
CNR	12.5	(4.3)	11.4	(3.1)	13.5	(3.9)	15.3	(4.7)	<0.001	0.002	<0.001	<0.001	<0.001	<0.001	<0.001

Values are given in arithmetic mean (SD); reconstruction with filtered back projection/ quantum denoising filtering system (FBP/QDS), adaptive iterative dose reduction (AIDR) 3D mild (MILD), standard (STD) and strong (STR); The values of all measurement points are summarised; First, Repeated Measures ANOVA overall analysis including every measurement point as dependent variable showed p<0.001 (p ANOVA) for signal, noise, SNR and also CNR. Subsequently, t-test was used as single test for the 4 quantitative parameters. Bonferroni correction was automatically performed for the multiple testing with 6 possibilities: p1 (FBP/QDS-AIDR 3D mild), p2 (FBP/QDS-AIDR 3D standard), p3 (FBP/QDS-AIDR 3D strong), p4 (AIDR 3D mild-AIDR 3D standard), p5 (AIDR 3D mild-AIDR 3D strong), p6 (AIDR 3D standard-AIDR 3D strong); signal presents the density in Hounsfield Units; noise is SD of the signal; SNR = signal in the vessel measurement point/noise in the aorta ascendens measurement point; CNR = (signal in the surrounding tissue of the vessel measurement point—signal in the vessel measurement point)/noise in the aorta ascendens measurement point.