. Author manuscript; available in PMC: 2012 Jul 1.

Published in final edited form as: Magn Reson Imaging. 2011 May 14;29(6):819–826. doi: 10.1016/j.mri.2011.02.017

Table 2.

Comparisons of summary statistics between select combinations of noise correction.

Correction Comparison	%Δ σ		%Δ Max R²_a
Field Strength:	1.5 T	3.0 T	1.5 T	3.0 T
RB vs. none	-1.63 ^#	-1.93	2.87	2.86
PPG vs. none	-1.59	-1.59	-0.19 ^#	3.12
RETROICOR vs. none	-8.17 ^#	-10.35	44.08 ^* ^#	66.44 ^*
[RETROICOR + ETCO₂] vs. RETROICOR	-1.84	-2.44	-2.62 ^#	0.84
[RETROICOR + ETCO₂] vs. none	-9.86 ^#	-12.54	40.32 ^* ^#	67.84 ^*

Correction Comparison	%Δ Mean R² _a		%Δ Activation
Field Strength:	1.5 T	3.0 T	1.5 T	3.0 T

RB vs. none	56.82 ^*	37.05 ^*	-7.04 ^#	3.24
PPG vs. none	57.98 ^* ^#	33.77 ^*	-0.36	-0.5
RETROICOR vs. none	227.32 ^* ^#	240.32 ^*	-15.79	-9.06
[RETROICOR + ETCO₂] vs. RETROICOR	-0.23 ^#	4.24	-9.18	-2.2
[RETROICOR + ETCO₂] vs. none	226.59 ^* ^#	254.76 ^*	-23.53	-11.06

Legend: Values listed are the percent difference in the parameter between the two analyses listed for comparison. RETROICOR includes both RB and PPG correction components. Statistical significance of the changes in summary statistics is indicated as follows:

significant change (p < 0.05) when implementing the correction (listed to left) for the data acquisition indicated (column headings);

significant difference between the 1.5 and 3.0 T acquisitions when comparing the impact of the same correction.