The Effect of Different Utility Measures on the Cost-Effectiveness of Bilateral Cochlear Implantation

Objectives/Hypothesis: To determine if the choice of health utility measure affects the incremental cost-utility ratio (ICUR) when assessing the cost-effectiveness of bilateral cochlear implantation (CI). Study Design: A scenario-based estimate with three scenarios: 1) a patient with severe to profound sensorineural hearing loss with no intervention, 2) the same patient with a unilateral CI with average or better performance, and 3) the same patient with bilateral CIs with average or better performance. Methods: One hundred and forty-two subjects comprising preimplantees (n = 30), unilateral cochlear implantees (n = 30), bilateral implantees (n = 30), and healthcare professionals (n = 52). The four health utility instruments applied were the Health Utility Index Mark 3 (HUI3), European Quality of Life Questionnaire in 5 Domains (EQ5D), visual analog scale (VAS), and time trade-off (TTO). Cost for each implant was based on a 25-year time horizon, 50% discount for the second implant, and a 15% failure rate. Results: Using the HUI3, the utility gain from unilateral to bilateral implantation was 0.035 or 11.5% of the total utility gain. This ratio was higher using the other instruments: EQ5D (22.2%), VAS (35.0%), and TTO (41.4%). For the scenario of bilateral CI compared to no intervention, HUI3 ICUR estimates were the lowest, and for bilateral CI compared to unilateral CI, HUI3 ICUR estimates were the highest. Conclusions: The choice of utility instrument in cost-utility analysis of bilateral CI heavily influences whether the second implant is deemed cost-effective. The HUI3 is the utility of choice in CI studies and is the most conservative.