Table A4.

List of features used in the logistic regression models. These features were obtained using two sets of DEVICE measurements from paired mass images when the same mass was measured in different conditions. For the intraoperator analysis, the pair of measurements were obtained from the same operator, whereas for the interoperator analysis, they were obtained by 2 different operators. The target displacement threshold of 10 mm was used as the binary label of logistic regression models to indicate whether a displacement was large, and all other features were used as predictors.

Features	Description	Controllable
Patient rotation R difference	$\left|R_1-R_2\right|$	Yes
Patient rotation E difference	$\left|E_1-E_2\right|$	Yes
Patient rotation H difference	$\left|H_1-H_2\right|$	Yes
Probe axial angle difference	$\left|{\beta }_1-{\beta }_2\right|$	Yes
Probe EA difference	$\widehat{{\mathrm{EA}}_1{\mathrm{EA}}_2}$ †	Yes
Probe orientation difference	$\left|{\alpha }_1-{\alpha }_2\right|$	Yes
2D probe center difference	${\displaystyle \Vert }\overrightarrow{{P^{\prime }}_1{P^{\prime }}_2}{\displaystyle \Vert }$	Yes
3D probe center difference	${\displaystyle \Vert }\overrightarrow{P_1{P}_2}{\displaystyle \Vert }$	Yes
Probe height difference	$\left|{\mathrm{P}\_\mathrm{height}}_1-{\mathrm{P}\_\mathrm{height}}_2\right|$	Yes
Probe CFP difference	$\left|{\mathrm{P}\_\mathrm{CFP}}_1-{\mathrm{P}\_\mathrm{CFP}}_2\right|$	Yes
Probe ratio difference	$\left|{\mathrm{P}\_\mathrm{ratio}}_1-{\mathrm{P}\_\mathrm{ratio}}_2\right|$	Yes
Probe 2DDN difference	$\left|{\mathrm{P}2\mathrm{DDN}}_1-{\mathrm{P}2\mathrm{DDN}}_2\right|$	Yes
Probe 3DDN difference	$\left|{\mathrm{P}3\mathrm{DDN}}_1-{\mathrm{P}3\mathrm{DDN}}_2\right|$	Yes
Greater target to skin	$max\left(T\_ski{n}_1, T\_ski{n}_2\right)$	No
Greater target to chest	$max\left(T\_ches{t}_{1,}T\_ches{t}_2\right)$	No
Greater target 3DDN	$\max \left({\mathrm{T}3\mathrm{DDN}}_1,{\mathrm{T}3\mathrm{DDN}}_2\right)$	No
Greater target 2DDN	$max\left(T2DD{N}_1,T2DD{N}_2\right)$	No
Greater target CFP	$\max \left({\mathrm{T}\_\mathrm{CFP}}_1,{\mathrm{T}\_\mathrm{CFP}}_2\right)$	No
Greater lesion volume	$\max \left({\mathrm{T}\_\mathrm{volume}}_1,{\mathrm{T}\_\mathrm{volume}}_2\right)$	No
Target displacement	${\displaystyle \Vert }\overrightarrow{T_1{T}_2}{\displaystyle \Vert }$

† The angle between two sets of Euler angles was calculated by determining the angular distance between corresponding quaternions.