Model
A literature review was performed to identify population PK models for intravenous tobramycin in CF adult patients. Models were included in this study if they were developed with NONMEM® software (Icon Development Solutions, Ellicott City, MD, USA) and if associated covariates were consistent with our collected data. Models were excluded if not enough data was provided to characterize the structural model.
Model evaluation
Previously published models were implemented on NONMEM® version 7.4.4. Visual evaluation of plots was conducted using R (version 3.5.1). An analysis of goodness of fit plot was performed to assess model validity. Indicators, according to the method of Varvel et al., were then calculated(11). The relative performance error (PEij[%] for the ith individual at the jth tobramycin concentration) was compared to the predicted concentration (Cpred ij) with the corresponding observations (Cobs ij) – Equation 1 :