Table 1.

Pairwise comparisons of mass-normalized DTT consumption rate estimates for each method, separated by concentration level.

Concentration Level	Method	Mean Reactivity ± SE (pmol DTT/min/μgpm)	P-value*
High	On-line	86.5 ± 10.4	0.22
	Traditional	66.0 ± 12.2
Middle	On-line	94.7 ± 10.0	0.33
	Traditional	110.5 ± 12.2
Low	On-line	96.9 ± 11.7	0.10
	Traditional	64.7 ± 12.2
Combined	On-line	92.7 ± 5.7	0.20
	Traditional	80.3 ± 7.1

^*P-values were estimated with two-tailed t-tests of difference in means between the two systems.