Table 1.

Quantitative results associated with the different dose levels in the projection space. The p value between the low-dose and the predicted standard-dose projections at each reduced dose level is given

Projection space
Parameters	HD	PHD	QD	PQD	OD	POD
PSNR	1.93 ± 33.22	1.33 ± 37.34	1.99 ± 28.25	1.56 ± 35.37	1.69 ± 24.51	1.77 ± 32.37
	p value < 0.001		p value < 0.001		p value < 0.001
SSIM	0.01 ± 0.96	0.01 ± 0.98	0.01 ± 0.93	0.01 ± 0.97	0.02 ± 0.89	0.01 ± 0.95
	p value < 0.001		p value < 0.001		p value < 0.001
RMSE	1.19 ± 5.69	0.52 ± 3.50	2.19 ± 10.10	0.78 ± 4.41	3.26 ± 15.52	1.23 ± 6.26
	p value < 0.001		p value < 0.001		p value < 0.001

HD half-dose, PHD predicted half-dose, QD quarter-dose, PQD predicted quarter-dose, OD one-eighth-dose, POD predicted one-eighth-dose