Table 5.

Difference in average, normalized AUC values for the full-dose FBP images and AIDR 3D (standard strength) images acquired at different dose levels for each size setting. Associated $p$-values from two-tailed student $t$-test are listed from each difference value.

Dose relative to full-dose FBP	Small		Medium		Large
	$\mathrm{\Delta }\overline{\widehat{\mathrm{AUC}}}$	$P$-value	$\mathrm{\Delta }\overline{\widehat{\mathrm{AUC}}}$	$P$-value	$\mathrm{\Delta }\overline{\widehat{\mathrm{AUC}}}$	$P$-value
100%	$+0.002$	0.4	$+0.019$	0.002	$+0.031$	0.0001
75%a	$-0.012$	0.05	$-0.004$	0.8	$+0.009$	0.4
50%	$-0.063$	0.005	$-0.048$	0.03	$-0.039$	0.03
33%	$-0.106$	0.001	$-0.094$	0.0002	$-0.071$	0.0015
25%b	$-0.124$	0.002	$-0.124$	0.00	—	—

^aIndicates 77% dose for the small and medium size settings.

^bIndicates 22% dose for the medium size setting.