Table 2 Recommended values used in the assessing of the QSAR model

R²

Coefficient of determination

≥ 0.6

P_(95%)

Confidence interval at 95% confidence level

< 0.05

Q²

Squared cross-validation coefficient

≥ 0.5

R²-Q²

Difference between R² and Q²

< 0.3

N_{test set}

Least number of test set

≥ 5

R²_ext

Coefficient of determination of external validation

≥ 0.5