Introduction
Various factors, including an aging population and expanding eligibility criteria, may increase the demand for cochlear implants (CIs), potentially resulting in longer waiting times. In most Dutch CI centers, the time between referral and surgery exceeds 6 months. Clinical experience suggests that during the waiting period for cochlear implantation, hearing and communication difficulties increase. Simultaneously, there is an interest in outcomes more closely aligned with patient values and needs, which resulted in the SMILE (Societal Merit of Interventions on hearing Loss Evaluation) study. This paper presents results on observed changes in societal and participatory outcomes during waiting time in participants with a time to CI surgery exceeding 6 months.

Methods
SMILE is a prospective multi-center study including 232 individuals who were referred for unilateral CI. Continuous and nominal data from multiple questionnaires, sent immediately after referral and shortly before surgery, were analyzed by computing differences, Cohen’s D, and odds ratios.

Results
Of the total 232 participants, 102 had a time between inclusion and surgery exceeding 6 months. Of these, 89 had (partially) filled out surveys at both time points. Of all the domain scores 55% did not show differences between timepoints. All Cohen’s D estimates were relatively small, ranging from − 0.298 to 0.388 for those outcomes that showed noteworthy changes.

Conclusion
Waiting time from referral to surgery, even though exceeding 6 months, was observed to not seriously affect non-clinically-prioritized patients in an adverse way. Future investigations should identify subgroups on tolerable waiting times regarding short- and long-term outcomes.

Trial registration
Trial registration number at ClinicalTrials.gov: NCT05525221, 25-8-2022.

Objective: To assess the impact of cochlear implantation (CI) and speech perception outcomes on the quality of life (QoL) of adult CI users and their communication partners (CP) one-year post-implantation. Design: This research is part of a prospective multicenter study in The Netherlands, called SMILE (Societal Merit of Intervention for hearing Loss Evaluation). Study sample: Eighty adult CI users completed speech perception testing and the Nijmegen Cochear Implant Questionnaire (NCIQ). Fifty-four CPs completed the Hearing Impairment Impact–Significant Other Profile (HII-SOP). Results: CI resulted in a large improvement in the QoL of both users and CPs. Despite this, some users still reported difficulties in the NCIQ sub-domains Social Interactions, Activity Limitations and Self-esteem. Similarly, some CPs still reported moderate and severe third-party disability on the HII-SOP. Additionally, the correlation between speech perception results and self-reported QoL was weak to negligible for both groups. Conclusions: Speech perception in quiet is not an accurate measure of real-life success with a CI. A subset of CI users and CPs still experience substantial QoL challenges regardless of speech perception performance. To improve counselling and intervention, QoL measures should be a standard part of the CI care pathway for CI users and their CPs.