Table 2.

displays bivariate Spearman's rank correlation coefficients (* denotes p < 0.05, two-tailed) for the results from metabolic validation in comparison to both the metrics from the proposed Formula 1 (see Fig. 2) as well as previously described QICGFA

Spearman’s rank correlation coefficients
	Metabolic		New formula				Conventional QICGFA
	Lactate (mg/dl)	Lactate ratio	Scale factor	Diff. in curve area	Fit peak	Fit accepted	Upslope	T1/2	Fmax	Tmax	Dslope	T50	F50	D50	T100	F100	D100	TR	C.M
Lactate concentration (mg/dl)	1.00	0.61*	− 0.10	0.29	0.16	− 0.48*	− 0.27	− 0.22	− 0.50*	− 0.21	− 0.64*	0.46*	− 0.43*	− 0.56*	0.46*	− 0.48*	− 0.51*	0.19	0.32*
Lactate ratio	0.61*	1.00	0.22	0.32*	0.04	− 0.49*	− 0.31*	− 0.20	− 0.56*	− 0.22	− 0.50*	0.33*	− 0.48*	− 0.50*	0.33*	− 0.51*	− 0.49*	0.26	0.15
Scale factor	− 0.10	0.22	1.00	0.16	− 0.58*	0.04	0.16	− 0.08	− 0.09	− 0.06	0.02	− 0.34*	− 0.15	0.00	− 0.34*	− 0.13	− 0.01	− 0.13	− 0.21
Diff. in curve area	0.29	0.32*	0.16	1.00	0.44*	− 0.74*	− 0.48*	− 0.45*	− 0.62*	− 0.45*	− 0.36*	0.30*	− 0.63*	− 0.55*	0.30*	− 0.53*	− 0.64*	0.42*	− 0.04
fit peak	0.16	0.04	− 0.58*	0.44*	1.00	− 0.48*	− 0.42*	− 0.16	− 0.21	− 0.18	− 0.15	0.61*	− 0.16	− 0.31*	0.61*	− 0.12	− 0.33*	0.40*	0.28
Fit accepted	− 0.48*	− 0.49*	0.04	− 0.74*	− 0.48*	1.00	0.64*	0.43*	0.54*	0.43*	0.52*	− 0.44*	0.46*	0.62*	− 0.44*	0.43*	0.64*	− 0.51*	− 0.19
Upslope	− 0.27	− 0.31*	0.16	− 0.48*	− 0.42*	0.64*	1.00	0.70*	0.56*	0.70*	0.41*	− 0.32*	0.46*	0.53*	− 0.32*	0.52*	0.52*	− 0.92*	− 0.01
T1/2	− 0.22	− 0.20	− 0.08	− 0.45*	− 0.16	0.43*	0.70*	1.00	0.62*	0.99*	0.37*	− 0.01	0.66*	0.36*	− 0.01	0.68*	0.37*	− 0.72*	0.16
Fmax	− 0.50*	− 0.56*	− 0.09	− 0.62*	− 0.21	0.54*	0.56*	0.62*	1.00	0.64*	0.51*	− 0.37*	0.94*	0.82*	− 0.37*	0.93*	0.86*	− 0.60*	0.21
Tmax	− 0.21	− 0.22	− 0.06	− 0.45*	− 0.18	0.43*	0.70*	0.99*	0.64*	1.00	0.37*	− 0.02	0.68*	0.37*	− 0.02	0.70*	0.38*	− 0.74*	0.17
Downslope	− 0.64*	− 0.50*	0.02	− 0.36*	− 0.15	0.52*	0.41*	0.37*	0.51*	0.37*	1.00	− 0.14	0.42*	0.52*	− 0.14	0.45*	0.49*	− 0.29	− 0.30
T50	0.46*	0.33*	− 0.34*	0.30*	0.61*	− 0.44*	− 0.32*	− 0.01	− 0.37*	− 0.02	− 0.14	1.00	− 0.27	− 0.47*	10.00*	− 0.27	− 0.51*	0.30	0.50*
F50	− 0.43*	− 0.48*	− 0.15	− 0.63*	− 0.16	0.46*	0.46*	0.66*	0.94*	0.68*	0.42*	− 0.27	1.00	0.61*	− 0.27	0.97*	0.68*	− 0.50*	0.27
D50	− 0.56*	− 0.50*	0.00	− 0.55*	− 0.31*	0.62*	0.53*	0.36*	0.82*	0.37*	0.52*	− 0.47*	0.61*	1.00	− 0.47*	0.62*	0.97*	− 0.53*	0.05
T100	0.46*	0.33*	− 0.34*	0.30*	0.61*	− 0.44*	− 0.32*	− 0.01	− 0.37*	− 0.02	− 0.14	10.00*	− 0.27	− 0.47*	1.00	− 0.27	− 0.51*	0.30	0.50*
F100	− 0.48*	− 0.51*	− 0.13	− 0.53*	− 0.12	0.43*	0.52*	0.68*	0.93*	0.70*	0.45*	− 0.27	0.97*	0.62*	− 0.27	1.00	0.65*	− 0.55*	0.26
D100	− 0.51*	− 0.49*	− 0.01	− 0.64*	− 0.33*	0.64*	0.52*	0.37*	0.86*	0.38*	0.49*	− 0.51*	0.68*	0.97*	− 0.51*	0.65*	1.00	− 0.52*	0.06
TR	0.19	0.26	− 0.13	0.42*	0.40*	− 0.51*	− 0.92*	− 0.72*	− 0.60*	− 0.74*	− 0.29	0.30	− 0.50*	− 0.53*	0.30	− 0.55*	− 0.52*	1.00	− 0.11
C.M	0.32*	0.15	− 0.21	− 0.04	0.28	− 0.19	− 0.01	0.16	0.21	0.17	− 0.30	0.50*	0.27	0.05	0.50*	0.26	0.06	− 0.11	1.00

Diff difference, T time, F fluorescence, D downslope, 50 and 100 denote time after Tmax. TR is a previously described ratio of T1/2 and Tmax, C.M. centre of mass