Figure 2.

Goodness-of-fit plot for the final model, normalized prediction distribution errors. The upper frame shows normalized prediction distribution errors (npde) vs. duration of epinephrine perfusion (delay C₀ to C₁) and the lower frame npde vs. model-predicted concentrations. The npde distribution was not significantly different from normality (P = 0.10 by Shapiro-Wilks test). Npde statistics are based on estimates of unbiased means and variances of the observations using 500 Monte Carlo simulations of the final model (the calculations include a de-correlation step of the prediction errors).