Incremental Cost Component Bridge
Compare matching cost components while preserving the comparator, analytical boundary, timing and discounting.
Incremental cost = intervention cost − comparator cost. A negative result means the intervention is less costly under the stated assumptions. A modelled cost offset is not automatically a cash-releasing saving.
1. Analytical boundary
2. Cost components
| Component | Time | Intervention | Comparator | PV difference |
|---|
Time 0 is not discounted. Fractional years are supported. Use negative component values only for genuine credits, rebates or net reductions.
3. Reconciliation
Calculate to audit the bridge.
4. Simple uncertainty scenario
Interpretation safeguards
- Use the same population, perspective, horizon, currency, price year and costing rules for both alternatives.
- Keep subtraction direction consistent.
- Component differences must reconcile to the difference between total costs.
- Cost offsets are not automatically cash-releasing savings.
- Incremental cost alone does not establish cost-effectiveness, dominance, affordability or adoption.
- Scenario analysis should show which assumptions can materially change the sign or size of incremental cost.