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. Author manuscript; available in PMC: 2009 Dec 30.
Published in final edited form as: Neuroimage. 2009 May 27;47(4):1506–1513. doi: 10.1016/j.neuroimage.2009.05.045

Table 2.

Absolute percentage scale corrections calculated using the phantom for baseline scans and repeat scans.

X-axis (%) Y-axis (%) Z-axis (%) Volume (%)
Baseline Mean (SD) 0.41 (0.39) 0.56 (0.26) 0.40 (0.32) 0.90 (0.69)
Baseline Range 0.03–2.18 0.05–1.65 0.01–1.54 0.00–3.42
Repeat Mean (SD) 0.38 (0.36) 0.53 (0.30) 0.43 (0.36) 0.87 (0.69)
Repeat Range 0.01–2.03 0.01–1.59 0.00–1.67 0.01–2.25
Baseline/repeat Mean (SD) 0.20 (0.27) 0.17 (0.20) 0.14 (0.16) 0.33 (0.36)
Baseline/repeat Range 0.00–1.39 0.00–1.21 0.00–0.71 0.00–1.66

For each image in our phantom corrected dataset, we have the scale factor calculated using the phantom for each axis. We calculate the volume change as X × Y × Z for each image and convert to an absolute percentage, and display the mean (SD) and range aggregated over the 129 baseline images (rows 1, 2) and the 129 repeat images (rows 3, 4). Furthermore, we take the baseline and repeat volume scale factors, and calculate the ratio of Baseline/Repeat, and display the mean (SD) and range in rows 5 and 6.