A CEAC demonstrates increasing probability of cost-effectiveness as WTP increases. What does this suggest?

• A. The intervention becomes more acceptable at higher WTP thresholds
• B. It becomes less acceptable at higher WTP thresholds
• C. It shows fixed probability
• D. It is inconclusive

Answer: (A)

A Cost-Effectiveness Acceptability Curve (CEAC) tracks the chance that an intervention is cost-effective at different willingness-to-pay (WTP) thresholds for a unit of health gain. If the CEAC shows the probability of cost-effectiveness increasing as the WTP threshold rises, it means that as decision-makers are willing to pay more for each unit of effect, more of the uncertain outcomes fall below that threshold. In practical terms, the intervention becomes more acceptable at higher WTP values because the price you’re willing to pay per unit of effect makes the intervention look cost-effective in a larger share of possible scenarios. It’s not a fixed probability, and the rising curve doesn’t imply inconclusive results; it simply reflects greater affordability or value from the payer’s perspective as the WTP increases.