Table 2.

Median (standard deviation) relative tumor activity error of 4 methodologies in all acquisitions and in each tumor depth and eccentricity sub-group.

	All Depth	Mid-Breast			Edge-Breast
	All Eccentricity	None	Low	High	None	Low	High
N (%)	4,024 (100%)	352 (9%)	976 (24%)	1,260 (31%)	153 (4%)	524 (13%)	759 (19%)
$A_t^{near}$	0.2% (4.3%)	0.1% (3.6%)	0.5% (4.4%)	0.2% (4.2%)	0.2% (4.0%)	0.3% (4.5%)	−0.5% (4.4%)
$A_t^{far}$	1.6% (4.4%)	0.5% (4.0%)	1.4% (4.3%)	1.4% (4.0%)	2.5% (5.2%)	2.8% (5.0%)	2.1% (4.1%)
$A_t^{gm\ast }$	4.6% (14.5%)	6.8% (20.8%)	3.5% (12.4%)	4.5% (13.5%)	3.1% (10.0%)	3.5% (12.4%)	4.0% (11.3%)
$A_t^{gm}$	8.1% (5.8%)	10.2% (5.9%)	6.7% (5.9%)	8.2% (5.3%)	9.6% (5.9%)	6.7% (5.9%)	5.9% (5.4%)