TABLE 3

Results of ROC analysis for defining cutoff values of physicochemical properties, to predict compounds with negligible (<10%) or significant (≥10%) rat BE

Properties	All Compounds (n = 286)		All Compounds with Molecular Mass ≥ 400 (n = 174)		All Acids (n = 116)
Properties	ROC Curve AUC	Cutoff^{^a}	ROC Curve AUC	Cutoff^{^a}	ROC Curve AUC	Cutoff^{^a}
Molecular mass, Da	0.72	400			0.81	400
cLogD_7.4	0.67	2.9	0.79	2.0	0.68	1.9
Permeability, 10⁻⁶ cm/s	0.78	2.8	0.73	2.5	0.81	2.6
PSA, Å²	0.77	85	0.73	93	0.85	88
%Relative PSA	0.64	19	0.76	20	0.62	20

↵a When ROC curve did not yield a point with both sensitivity and specificity above 0.8, the cutoff was assigned to the value that showed sensitivity of 0.8.