Table 5.
Standard errors (expressed as coefficient of variation) for the population mean and between-subject variability for parameters under the different structural models under consideration
| Parameter | M1 | M2 | M3 | M4 | M5 | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| popt CV (%) | nonmem CV (%) | popt CV (%) | nonmem CV (%) | popt CV (%) | nonmem CV (%) | popt CV (%) | nonmem CV (%) | popt CV (%) | nonmem CV (%) | |
| Population mean | ||||||||||
| CL | 5.5 | 6.1 | 5.6 | 4.9 | 5.6 | 5.3 | 5.6 | 6.1 | – | – |
| V | 4.4 | 3.9 | 4.3 | 4.4 | 4.3 | 4.0 | 4.3 | 3.8 | 4.4 | 9.2 |
| Ka | 42 | 35 | 42 | 40 | 42 | 35 | 42 | 36 | 42 | 50 |
| Fabs | 7.6 | 8.7 | 7.5 | 8.1 | 9.7 | 9.6 | 9.8 | 11 | 7.5 | 8.1 |
| Kmn | – | – | – | – | 36 | 27 | 50 | 50 | – | – |
| CL_int | – | – | – | – | – | – | – | – | 44 | 6.2 |
| Km1 | – | – | – | – | – | – | – | – | 84 | 19 |
| Fmaxreabs | – | – | – | – | – | – | – | – | 11 | FIX |
| Between-subject variability | ||||||||||
| VAR(CL) | 38 | 38 | 39 | 38 | 39 | 39 | 39 | 39 | – | – |
| VAR(V) | 40 | 40 | 39 | 38 | 40 | 37 | 40 | 39 | 40 | 44 |
| VAR(Ka) | 32 | 42 | 32 | 46 | 33 | 55 | 33 | 40 | 32 | 13 |
| VAR(Fabs) | 36 | 35 | 35 | 38 | 34 | 38 | 34 | 35 | 36 | 39 |
| VAR(CL_int) | – | – | – | – | – | – | – | – | 60 | 29 |
| VAR(Fmaxreabs) | – | – | – | – | – | – | – | – | 37 | – |
| Residual variability | ||||||||||
| VAR(prop) | 7.4 | 14 | 6.8 | 14 | 7.4 | 14 | 7.3 | 14 | 7.8 | 12 |
| VAR(add) | NE | 19 | NE | 42 | NE | 27 | NE | 23 | NE | 32 |
CL, clearance; V, central volume of distribution; Ka, absorption rate constant; Fabs, fraction absorbed; Kmn, drug dose at half of Fmin; CL_int, intrinsic clearance; Km1, drug dose at half of CLrmax; Fmaxreabs, maximum reabsorbed fraction.