LAUSR

7 days (Figure 1). These clearance and terminal half-life values therefore make it difficult to reconcile the presented PTA curves and model parameter estimates, in particular for the older (7–14 and 14–28 day) age groups. For example, Darlow and Hope report an approximate PTA of 70%–90% for 40% time above 1 mg/L, which does not appear to accordwith a typical pharmacokinetic profile plot from their reportedmodel parameters (Figure 1). Caution should therefore be taken in using this model to infer dosing and this example highlights a limitation of ignoring biological priors in the parameter structure of neonatal pharmacokinetic covariate models.