Fig. 2. The measured/predicted plasma concentrations of dexmedetomidine versus time for the best model estimated by NONMEM, based on the typical values (population model , top ), and the individual post hoc Bayesian estimates of volume and clearance in each child (individual models , bottom ). The line of unity appears as a solid horizontal line in both graphs. Overall, the quality of the fit was quite good, with little suggestion of model misspecification.