Objectives: To evaluate the benefits of cochlear implantation in postlingually deafened adults and estimate the clinical relevance of these benefits.
Study design: Prospective intervention study.
Setting: Tertiary referral hospital.
Patients: Forty-four postlingually deafened adults.
Interventions: Cochlear implantation with a Clarion CII HiFocus 1 or HiRes 90K.
Main outcome measures: The Health Utility Index Mark II (HUI2) and Nijmegen Cochlear Implant Questionnaire were administered to quantify health-related QoL (HRQoL); utilities were obtained from the HUI2 and time trade-off instrument. Speech perception scores were analyzed. Patient factors were correlated with postimplant HRQoL and speech perception scores. Clinical significant benefit was estimated using the minimal clinically significant difference (MID) and effect size (ES).
Results: The results show a significant improvement in HRQoL and speech perception (p < 0.001). The improvement in HRQoL is mainly obtained in the first months after implantation and is largest in the categories concerning physical functioning (hearing). A shorter duration of deafness (p = 0.003) and higher educational level (p = 0.015) were significant predictors of better speech perception. Cochlear implantation proved to be a cost-effective procedure. By using the MID and ES, we found important clinical improvements on 6 health domains of the Nijmegen Cochlear Implant Questionnaire and on the sensation domain of the HUI2 in most patients; all but 1 of the ESs were large.
Conclusion: Cochlear implants have a large and significant positive impact on HRQoL and speech perception and are cost-effective. These improvements are clinically relevant as measured by the MID.