Baseline models
- to consider the baseline values observed before and after treatment
- e.g. endogenous synthesis of cortisol
- e.g. endogenous biomarker (17-OHP)
- 4 types of methods [📖]
B1
- individual baseline was derived considering IIV (\(η_i\)) and the population baseline
- assuming a log-normal distribution of the baseline
- does not require pre-dose measurements
- seen as the gold standard
- independent of the data
- superior to the B2 method
\[baseline_𝑖 = baseline \cdot 𝑒^{𝜂_𝑖}\]
B2
- estimated \(baseline_i\) is informed by
- the individually observed initial concentration (\(baseline_{obs,i}\))
- the interindividual variability corresponding to the residual variability (\(η_i,RV\))
\[𝑏𝑎𝑠𝑒𝑙𝑖𝑛𝑒_𝑖=𝑏𝑎𝑠𝑒𝑙𝑖𝑛𝑒_{𝑜𝑏𝑠,𝑖} \cdot 𝑒^{𝜂_𝑖,𝑅𝑉}\]
B3
- [TBA]
B4
- [TBA]