A COMPUTERIZED ADAPTIVE TESTING SYSTEM FOR SPEECH-DISCRIMINATION MEASUREMENT - THE SPEECH SOUND PATTERN-DISCRIMINATION TEST

A computerized, adaptive test-delivery system for the measurement of s peech discrimination the Speech Sound Pattern Discrimination Test, is described and evaluated. Using a modified discrimination task, the tes ting system draws on a pool of 130 items spanning a broad range of dif ficulty to estimate an examinee's location along an underlying continu um of speech processing ability, yet does not require the examinee to possess a high level of English language proficiency. The system is dr iven by a mathematical measurement model which selects only test items which are appropriate in difficulty level for a given examinee, there by individualizing the testing experience. Test items were administere d to a sample of young deaf adults, and the adaptive testing system ev aluated in terms of respondents' sensory and perceptual capabilities, acoustic and phonetic dimensions of speech, and theories of speech per ception. Data obtained in this study support the validity, reliability , and efficiency of this test as a measure of speech processing abilit y. (C) 1997 Acoustical Society of America.