Surveying the Cost-Effectiveness of the 20 Procedures with the Largest Public Health Services Waiting Lists in Ireland: Implications for Ireland's Cost-Effectiveness Threshold.

Objectives: To survey the cost effectiveness of procedures with the largest waiting lists in the Irish public health system to inform a reconsideration of Ireland's current cost-effectiveness threshold of €45,000/quality-adjusted life-year (QALY).

Methods: Waiting list data for inpatient and day case procedures in the Irish public health system were obtained from the National Treatment Purchase Fund. The 20 interventions with the largest number of individuals waiting for inpatient and day case care were identified. The academic literature was searched to obtain cost-effectiveness estimates from Ireland and other high-income countries. Cost-effectiveness estimates from foreign studies were adjusted for differences in currency, purchasing power parity, and inflation.

Results: Of the top 20 waiting list procedures, 17 had incremental cost-effectiveness ratios (ICERs) lower than €45,000/QALY, 14 fell below €20,000/QALY, and 10 fell below €10,000/QALY. Only one procedure had an ICER higher than the current threshold. Two procedures had ICERs reported for different patient and indication groups that lay on either side of the threshold.

Conclusions: Some cost-effective interventions that have large waiting lists may indicate resource misallocation and the threshold may be too high. An evidence-informed revision of the threshold may require a reduction to ensure it is consistent with its theoretical basis in the opportunity cost of other interventions foregone. A limitation of this study was the difficulty in matching specific procedures from waiting lists with ICER estimates from the literature. Nevertheless, our study represents a useful demonstration of a novel concept of using waiting list data to inform cost-effectiveness thresholds.