The French MBAA2 sentence recognition in noise test for cochlear implant users.

OBJECTIVE: The "Marginal benefit from acoustic amplification" version 2 (MBAA2) sentence test has been used in France in the routine evaluation of cochlear implant (CI) users for 20 years. Here we present four studies that characterise and validate the test, and compare it with the French matrix sentence test. DESIGN AND SAMPLE: An analytic method was developed to obtain speech recognition threshold in noise (SNR50) from testing at a fixed signal to noise ratios (SNRs). Speech recognition was measured at several fixed SNRs in 18 normal-hearing listeners and 15 CI listeners. Then, the test-retest reliability of the MBAA2 was measured in an additional 15 CI listeners. Finally, list equivalence was evaluated in eight CI listeners. RESULTS: The MBAA2 test produced lower SNR50s and SNR50s were obtained in more CI listeners than with the French matrix test. For the MBAA2, the standard deviation of test-retest differences in CI listeners was around 1 dB SNR. Three lists had deviant difficulty and nine low item-to-total correlations. CONCLUSIONS: We propose to reduce the number of MBAA2 test lists to reduce variability. The MBAA2 test has high test-retest reliability for percent correct and SNR50, and is suitable for the assessment of cochlear implant patients.

Technical aids for speech understanding in cochlear implanted adults using cell-phones.

OBJECTIVES: The present study sought to assess (1) phone use habits and awareness of listening aids in adult cochlear implant bearers, and (2) objective and subjective benefit of listening aids for cell-phone communication. MATERIAL AND METHODS: A questionnaire was sent to 17 cochlear (Cochlear(®)) implanted adults to assess phone use and awareness of available listening aids. Speech perception without lip-reading was assessed in silence and in noise using Fournier dissyllabic word lists recorded on an iPhone 5C(®), with and without listening aids. Subjective benefit was assessed according to listening aid system. RESULTS: Sixty-five percent of adult cochlear implant bearers regularly used a phone with all kinds of correspondent. Eighty-eight percent phoned only in quiet conditions; 53% did not answer unknown callers; 71% never used listening aids. Speech discrimination scores for disyllabic words recorded on the phone were respectively 69%, 63%, 45% and 16% in quiet and 50, 60 and 70dB SPL noise. Speech perception in quiet and noise was improved by listening aids; the Roger system was the most beneficial, followed by the FM system, then the inductive system. CONCLUSION: Listening aids are effective, but little known by adult cochlear implant bearers.