Table 1.

Rate of change of ROI-averaged Hb, HbO₂, HbT, sO₂ and percentage of black pixels (%BP) signal during the short-term (75 min) longitudinal study. The goodness of fit, R², indicates how much of the signal variability is time dependent and the p-value whether the signal change (slope of the linear model) is significantly different from zero. The SSE reflects how similar the predicted values and measured data are, i.e. the closest SSE is to zero, the better the linear fit.

Animal		Signal change, min−1 (95% CI)	R2	p-value	SSE
1	Hb HbO2 HbT	0.013 (0.012, 0.015) 0.016 (0.013, 0.018) 0.030 (0.027, 0.033)	0.968 0.932 0.976	<0.001 <0.001 <0.001	0.037 0.117 0.142
	sO2	0.0031 (0.0025, 0.0038)	0.895	<0.001	0.007
	%BP	−0.278 (-0.392, -0.163)	0.679	<0.001	255
2	Hb HbO2 HbT	0.013 (0.013, 0.014) 0.014 (0.013, 0.015) 0.027 (0.026, 0.028)	0.981 0.995 0.995	<0.001 <0.001 <0.001	0.020 0.006 0.027
	sO2	0.0027 (0.0023, 0.0032)	0.923	<0.001	0.004
	%BP	−0.146 (-0.203, -0.0896)	0.704	<0.001	63
3	Hb HbO2 HbT	0.0079 (0.0066, 0.0091) 0.0071 (0.0060, 0.0082) 0.015 (0.013, 0.017)	0.930 0.934 0.938	<0.001 <0.001 <0.001	0.030 0.023 0.096
	sO2	0.00025 (3.148e-05, 0.00047)	0.267	0.049	0.001
	%BP	-0.0284 (-0.037, -0.020)	0.799	<0.001	1
4	Hb HbO2 HbT	0.0047 (0.0040, 0.0054) 0.0047 (0.0038, 0.0057) 0.0098 (0.0084, 0.011)	0.940 0.895 0.940	<0.001 <0.001 <0.001	0.009 0.017 0.039
	sO2	0.0029 (0.0022, 0.0035)	0.857	<0.001	0.009
	%BP	−0.081 (-0.118, -0.043)	0.622	<0.001	28