Table 2.

i.i.d. performance across 10 sites. The average loss values over entire validation dataset are shown for the structural similarity index measure (SSIM) and normalized root mean squared error (NRMSE). Top performing values are shown in bold font.

Algorithm	SSIM ↑	Increase	NRMSE ↓	Decrease
Centralized	0.708	–	0.135	–
FedAvg	0.710	$+0.28\%$	0.134	$-1\%$
FedAdam	0.713	$+0.71\%$	0.151	$+12\%$
FedYogi	0.712	$+0.57\%$	0.138	$+2\%$
FedAdaGrad	0.712	$+0.57\%$	0.139	$+3\%$
Scaffold	0.711	$+0.42\%$	0.130	$-4\%$
FL-MRCM	0.489	$-31\%$	0.167	$+23\%$