Decision Network

A decision network is a Bayesian Network with added action nodes and utility nodes (also called value node) that enable decision making.

Here, the treatment is an action node and U is the utility node.

![[CleanShot 2023-09-28 at 10.54.29@2x.png]]

Construction

1. Create a causal model, a Graph with nodes for symptoms, disorders, treatments, outcomes and their influences
2. Simplify by removing Random Variables that are not involved in the treatment decision
3. Assign probabilities to the CPTs via patient databases, literatur studies or experts knowledge. This makes it a Bayesian Network
4. Assign utilities in the form of QALYs or Micromorts
5. Verify and refine the model by e.g. running the model backwards an comparing the values with the literature
6. Perform a Sensitivity Analysis to see whether the optimal decision is robust against changes in the parameters