Disease progression inverse Bateman

FIGURE 21.10 Example profile of inverse bateman disease progression model with symptomatic drug action. 

Cyclical Modification of Inverse Bateman Function A cosine function can be used to describe patterns similar to the exponential and inverse Bateman models and can therefore be used as the function for disease progress. However, this same cosine function can also be used to impose a cyclical modulation on another function. 

In this equation, the disease progression model is evaluated at any time t and the cosine function is added to the overall disease progression model to determine the status. Here, SADamp and Phase define the amplitude of the underlying cyclical change in disease severity score and the time to the maximum worsening of that score. A plot of an inverse Bateman function with a cyclical component is provided in Figure 21.11. 

---