OLSA level control in monaural speech audiometry in background noise for the evaluation of the CI fitting result

Abstract

Scientific background: Speech audiometry measurements under the influence of background noise are a fundamental part of evaluating the outcome of hearing care. As yet far, there are no recommendations for selecting a suitable method for adaptive speech audiometry measurements in background noise in cochlear implant (CI) care, so either the choice the adaptive level change of the speech signal (S) with constant noise (N) or the adaptive level change of N with constant S. Objectives: Do the measurement results of the monaural speechrecognition threshold in noise (SRT) with the Oldenburg Sentence Test (OLSA) depend on the choice of level control? Material and methods: A total of 50 series of measurements with OLSA in noise and the Freiburg speech intelligibility test in quiet (FBE) on middle-aged CI patients from clinical routine. Results: There is no significant difference in the measurement results with different level controls when the SRT is less than 5 dB S/N . Below 55 % monosyllabic intelligibility in quiet, the SRT in noise becomes greater than 5 dB S/N . Conclusion: From a clinical, audiological and methodological point of view, it is advisable to carry out the adaptive monaural speech intelligibility measurement with a constant speech signal at 65 dB SPL .