Table 3.
Population pharmacokinetic parameter estimates, inter‐individual variability, and median parameter values (2.5–97.5%) of the non‐parametric bootstrap replicates of the final pharmacokinetic model of oxycodone
| Parameters | Estimates (RSE, %) | CV (%) | Median (2.5–97.5%) |
|---|---|---|---|
| V 1 (l) = θ 1 + θ 2 × (LBM‐47) | |||
| θ 1 | 11.8 (11.4) | 30.5 | 13.5 (10.6–30.1) |
| θ 2 | 0.36 (31.4) | 0.393 (0.094–0.769) | |
| V 2 (l) = θ 3 + θ 4 × (LBM‐47) | |||
| θ 3 | 29.3 (7.3) | 21.1 | 31.0 (25.7–132) |
| θ 4 | 0.671 (41.3) | 0.733 (0.101–2.07) | |
| V 3 (l) = θ 5 + θ 6 × (LBM‐47) | |||
| θ 5 | 121 (2.7) | 12.9 | 122 (113–150 000) |
| θ 6 | 1.48 (23.9) | 1.24 (0.0001–31.55) | |
| CL (l/min) = θ 7 ‐(age/58) θ8 | |||
| θ 7 | 1.58 (1.7) | 26.2 | 1.56 (0.09–1.61) |
| θ 8 | 0.203 (40.2) | 0.216 (0.0008–0.692) | |
| Q 1 (l min −1 ) | 2.52 (15.3) | 48.1 | 2.78 (2.02–3.81) |
| Q 2 (l min −1 ) | 1.81 (11.4) | 42.9 | 1.71 (0.37–2.04) |
| σ 1 | 0.185 (10.5) | — | 0.145 (0.001–0.362) |
| σ 2 | 0.081 (1.745) | — | 0.085 (0.057–0.154) |
A log‐normal distribution of inter‐individual random variability was assumed. Residual random variability was modelled using an additive (σ1) plus proportional (σ2) error model. Non‐parametric bootstrap analysis was repeated 2000 times. RSE, relative standard error = SE/mean × 100 (%). LBM, lean body mass calculated using the Janmahasatian formula 24.