Validation of the equivalency and inherent variability in the newly formed sentence lists was accomplished by testing 15 cochlear implant users on all 33 sentence lists. Participants had monosyllabic word scores of 36 to 88 percent correct (avg = 61%, s.d. = 16). To avoid ceiling effects, sentence lists were presented in +5 dB SNR (multi-talker noise) for subjects with word scores of 85% or greater, +10 dB SNR for subjects with word scores between 65% and 84%, and in quiet for subjects with word scores below 65%. Sentence list order was randomized for each subject and lists were tested in 5 blocks, each containing 7 lists. For each subject, the final list of block 1 was repeated as the final list of blocks 3 and 5, resulting in a total of 35 test lists. Only the score from the first presentation of each list was considered in the validation analysis.
During testing, subjects were seated in a sound-treated booth. Sentences were presented at 60 dB SPL in the sound field from a single loudspeaker at 0 degrees azimuth on the horizontal axis. Subjects were instructed to repeat back each sentence and to guess when unsure of any word. Prior to testing, subjects completed a practice list of 50 sentences that were not included in the 33 lists. Following completion of each block of sentence lists, subjects were asked to exit the sound booth and relax for a minimum of 15 minutes. Each sentence was scored as the number of words repeated correctly and a percent correct score was calculated for each list.
During testing, subjects were seated in a sound-treated booth. Sentences were presented at 60 dB SPL in the sound field from a single loudspeaker at 0 degrees azimuth on the horizontal axis. Subjects were instructed to repeat back each sentence and to guess when unsure of any word. Prior to testing, subjects completed a practice list of 50 sentences that were not included in the 33 lists. Following completion of each block of sentence lists, subjects were asked to exit the sound booth and relax for a minimum of 15 minutes. Each sentence was scored as the number of words repeated correctly and a percent correct score was calculated for each list.
