Table 2.

Correlations between PRESS and three MEGA-PRESS measures of glx

	Controls (n=25)		Patients (n=17)		All (n=42)
	r (r²) with PRESS	CoV (%)	r (r²) with PRESS	CoV (%)	r (r²) with PRESS	CoV (%)
PRESS	---	11.9	---	9.8	---	10.9
MP-Off	0.88 (0.77)	9.2	0.76 (0.58)	8.9	0.84 (.70)	9.0
MP-Diff	0.16 (0.03)^**	10.1	0.44 (0.20)^a	8.8	0.26 (.07)^**	9.7
MP-Diff-PI	0.36 (0.13)^**	10.2	0.49 (0.24)^a	11.0	0.40 (.16)^**	11.0

Abbreviations as in Table 1; MP-Diff-PI = MEGA-PRESS difference spectra with glx/creatine quantified by peak integration, all others are glx/creatine from LCModel fits. Note that since peak integration cannot estimate glutamate separately from glutamine, peak integration values are only shown in Table 2.

^**

lower than PRESS vs MP-Off correlation, p < .0001

lower than PRESS vs MP-Off correlation, p < .05

NS, p ≤ .14