TABLE 7

Effect of data quality on the slope factor β

	Number of Fits	β (Average)^{^a}	%CV^{^b}	Min^{^c}	Max^{^c}
IC₅₀ fits from all laboratories for all data sets with t_β > 3 (Bentz et al., 2013)^{^a}
MDCK	48	1.3	50	0.3	3.6
Caco-2	70	1.1	31	0.6	2.4
LLC-PK	13	1.4	64	0.6	3.3
IC₅₀ fits from those laboratories which qualified in this work, e.g., t_β > 5^{^d}
MDCK	12	1.2	26	0.7	1.8
Caco-2	13	1.0	24	0.6	1.6
LLC-PK	4	1.2	9	1.0	1.2

↵^a Total number of fitted data sets (t_β > 3) for the slope factor β from Bentz et al. (2013) (Supplemental Data 2 of that paper).
↵^b Coefficient of variation for fitted β expressed as a percentage.
↵^c Minimum and maximum values for β.
↵^d These data are calculated from Table 2.