Figure 3.

(a) Coefficient of determination (r²) for individual midazolam sampling points and (b) mean squared prediction error (MSPE) for individual midazolam sampling points after 4 weeks of Ginkgo biloba extract administration. Comparison of area under the concentration-time curve from time 0 to infinity (AUC_0-∞) and single plasma concentrations for midazolam (0.5-8 hours postdose) when given after 4 weeks of Ginkgo biloba extract administration. Correlations were determined by regression analysis between individual midazolam concentrations and midazolam AUC_0-∞. Results are shown for prediction performance, assessed using coefficient of determination (r²) of (a) unweighted regression and (b) MSPE. Optimal sampling time, defined by the best predictive performance, occurs at the maximum r² and lowest MSPE.