AzBio Speech Understanding Performance in Quiet and Noise in High Performing Cochlear Implant Users

To evaluate high-performing cochlear implant patients' performance on AzBio sentence testing.

Retrospective review of prospectively collected database at a tertiary care hospital. Unilateral cochlear implant patients with AzBio testing were included. The primary outcome of interest was AzBio performance scores in quiet and at +10 and +5 decibels signal to noise (dB S/N).

One hundred eighty five subjects met inclusion criteria with scores for AzBio in quiet, 114 at +10 dB S/N, and 66 at +5 dB S/N. Linear mixed effects models showed performance significantly correlated with time since activation in all conditions (8.4%/yr; p < 0.0001). Strong correlations between mean performance in quiet and at +10 dB S/N (r = 0.77, p < 0.0001), and between +10 and +5 dB S/N (r = 0.73, p < 0.0001) were found. The correlation between quiet and +5 dB S/N (r = 0.45, p = 0.01) was less robust. Shapiro-Wilks test of normality found only +10 dB S/N to correspond to a normal distribution. Skew analysis demonstrated values of -0.64, -0.11, and 0.8 for quiet, +10 dB S/N, and +5 dB S/N, respectively.

AzBio scores at +10 dB S/N show a strong correlation with, but avoid the ceiling effects that limit the usefulness of testing in quiet for high performing cochlear implant users, making it the preferred test in this population. Significant complexities exist in the study of outcomes in cochlear implant recipients, and there is no single test that is ideal for the entirety of this population.