Decision Tree Rollback Explorer
Edit the terminal pathways for two treatment strategies. The explorer checks the probability structure, rolls costs and QALYs back to the decision node, and compares the strategies using incremental analysis and net monetary benefit.
HealthEconomics.wiki original learning tool · Version 1.0
1. Enter pathway values
Each strategy has three mutually exclusive terminal outcomes. Probabilities within each strategy must total 1.000.
Strategy A: New treatment
| Terminal outcome | Probability | Cost (£) | QALYs |
|---|
Strategy B: Standard care
| Terminal outcome | Probability | Cost (£) | QALYs |
|---|
2. Roll back and compare
Strategy A expected cost—
Strategy A expected QALYs—
Strategy B expected cost—
Strategy B expected QALYs—
Waiting for valid probabilitiesEach strategy must total one before rollback.
Decision-tree structure
A decision node branches to two strategy-specific chance nodes, each leading to three terminal outcomes.
Path probability = product of conditional probabilities
Expected cost = Σ(Pᵢ × Cᵢ)
Expected QALYs = Σ(Pᵢ × Eᵢ)
NMB = (λ × expected QALYs) − expected cost
Interpretation safeguard: The tree calculates expected values; it does not prove that the structure, probabilities, costs or outcomes are appropriate for a real decision.
| Measure | Strategy A | Strategy B | Incremental A−B |
|---|