AIM: The influence of bilateral cochlear implants (CI) and unilateral CI on the self-reported listening effort in standardized situations is being assessed.
SAMPLE AND METHODS: The sample consisted of 34 bilateral and 38 unilateral adult CI users. Unilateral CI users had at least severe hearing loss in the non-implanted ear and had been fitted with a hearing aid. The listening effort has been defined as a subjectively perceived effort in understanding a speaker. Patients were administered a customized questionnaire containing nine examples of listening situations with different demands. The listening effort expended in each situation had to be rated on a six-step scale. Answers were analyzed using repeated measures ANOVA, including the factors "level of background noise," "listening duration," and the covariates "patient age" and "time since CI implantation."
RESULTS: Only the factors "level of background noise" and "listening duration" were significant (p = 0.024 and p = 0.001 respectively). Unilateral versus bilateral CI was not significant (p = 0.17). Nevertheless, bilateral CI users reported a lower degree of listening effort than unilateral users in all of the nine situations asked about in the questionnaire (binomial test: p = 0.002).
DISCUSSION: We conclude that bilateral CI use has some effect on reducing listening effort, but compared with unilateral use the effect is possibly not very great.