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. Author manuscript; available in PMC: 2014 Oct 15.
Published in final edited form as: Neuroimage. 2013 May 24;80:10.1016/j.neuroimage.2013.05.077. doi: 10.1016/j.neuroimage.2013.05.077

Table 1.

Distribution of Functional QC measures.

Measure Meana Std Dev 5th percentile 95th percentile
tSNRb 24.41 2.39 20.37 28.04
FWHM: mean (mm) 1.66 0.080 1.56 1.82
AbsMotion: mean (mm) 0.31 0.21 0.13 0.72
RelMotion: mean (mm)c 0.093 0.029 0.06 0.15
RelMotion: 95th percentile (mm) 0.19 0.070 0.12 0.30
RelMotion > 0.15 (%)d 15.55 13.97 1.14 44.69
RelMotion > 0.30 (%)e 1.00 2.42 0.00 5.20
DVARS: mean (Δ% BOLD × 10)f 52.86 3.95 47.17 59.93
DVARS: std dev 2.98 2.50 1.01 6.85
a

N = 2207 task and resting-state fMRI runs (126 subjects)

b

temporal signal-to-noise ratio (mean divided by temporal standard deviation), computed voxelwise, then averaged over a whole brain mask

c

Relative motion as returned by FSL's MCFLIRT is approximately 1/2 of the “Framewise displacement” (FD) measure defined in Power et al. (2012).

d

Percentage of frames in the time series with relative motion > 0.15

e

Percentage of frames in the time series with relative motion > 0.30

f

DVARS returned by ‘fsl_motion_outliers’ is scaled to match the definition used in Power et al. (2012).