Fig. 4

Bland-Altman plot (difference between mean absorbed dose recovered in ¹⁶⁶Ho-DI and in ¹⁶⁶Ho-only against mean absorbed dose in ¹⁶⁶Ho-only) is depicted in the top row. Orange circles refer to pre-treatment dataset while blue diamonds to post-treatment. Mean of difference between absorbed dose recovered in ¹⁶⁶Ho-DI and in ¹⁶⁶Ho-only (\( {\overline{dose}}_{166\mathrm{Ho}-\mathrm{DI}}-{\overline{dose}}_{166\mathrm{Ho}-\mathrm{only}} \)) is depicted by the black solid line, while black dashed lines define ± limits of agreement. Data in (a) refers to VOI_HEALTHY, in (b) to VOI_TUMOR, and (c) depicts data referring to VOI_LUNGS. Linear correlation plot between ¹⁶⁶Ho-only and ¹⁶⁶Ho-DI with respect to the mean absorbed dose for VOI_HEALTHY (d), VOI_TUMOR (e), and VOI_LUNGS (f), subdivided between pre-treatment (circles) and post-treatment (diamonds), is reported in the bottom row. The solid line depicts linear regression, while the dashed lines indicate the ± 95% confidence intervals