The broad goal of the proposed research is development and commercialization of a multilevel model-based speech discrimination testing system designed for individuals experiencing speech discrimination difficulties ranging from mild to severe. Development of the testing system benefits from related research conducted over a 10-year period which resulted in a prototypic speech discrimination test for persons with severe to profound hearing losses. In the proposed work, we seek to increase the difficulty of the discrimination tasks and decrease test administration time. We perform detailed item, reliability and validity analyses to establish the empirical foundation fro a computerized, adaptive testing system responsive to the individual differences which exist among persons receiving audiological services. The test materials consist of sentence-level utterances presented to subjects with and without background noise. Fifty subjects will participate in the study. The testing system will be evaluated in terms of established psychometric criteria, and also for goodness-of-fit to a mathematical model for person measurement. This research represents and interdisciplinary collaboration. It is technically sophisticated in terms of current audiological practice, and has significant advantages over conventional methods of speech discrimination testing.
