Table 3.

Hippocampal segmentation and volumetry using FreeSurfer on the original, downsampled (at different coronal slice spacings), and SR scans. Using the segmentations and volumes computed from the 1 mm scans as ground truth, the table reports: the average % error in hippocampal volume; the correlation with the ground truth volumes; the Dice overlap with the ground truth segmentations; and the effect size of AD vs. controls (corrected for sex, intracranial volume and age). The slice thickness was 3 mm in all cases.

Slice spacing	Average vol. error	Corr. 1 mm	Dice 1 mm	Effect size
1 mm	0.0%	1.00	1.000	1.38
3 mm (cubic)	4.5%	0.98	0.891	1.35
3 mm (SynthSR)	3.3%	0.99	0.901	1.36
3 mm (fully sup.)	2.7%	0.99	0.909	1.36
5 mm (cubic)	7.6%	0.95	0.863	1.22
5 mm (SynthSR)	2.9%	0.99	0.889	1.33
5 mm (fully sup.)	2.7%	0.99	0.904	1.35
7 mm (cubic)	10.1%	0.91	0.835	0.98
7 mm (SynthSR)	3.0%	0.97	0.875	1.30
7 mm (fully sup.)	2.8%	0.99	0.900	1.34