Wayne M. Garrison

THE STUDENT INTEGRATION SURVEY: Development of an Early Alert Assessment and Reporting System

This study describes efforts to develop a self-report rating scale (Student Integration Survey: SIS) that provides diagnostic information about students with academic and/or social integration difficulties. Data obtained from administration of the SIS to incoming freshmen at a postsecondary technical institution for the deaf in the fall of 1990 and 1991 were subjected to Rasch rating scale analysis. Fit of data to the measurement model resulted in a set of 28 positive and negative statements that empirically defined the concept of “institutional integration” in terms of their calibration hierarchy. This type of instrument calibration has the potential of providing person measures and item scale values that are invariant over a useful range of comparisons. The early alert reporting system provides an evaluation and diagnosis of observed responses relevant to expected responses for individual respondees. The substance and methods employed may provide a model for other integration assessment efforts.

Reading Comprehension Test Item Difficulty As a Function of Cognitive Processing Variables

This study reports the results of a componential analysis of items comprising Sections A and C of Form Z of the reading comprehension portions of the California Achievement Tests (CAT) (Tiegs & Clark, 1963). A set of problem components or attributes characterizing the test items in terms of manifest content, psychologically salient features, and processing demands was developed, including methods for their quantification. The contributions of these components to task difficulty were then evaluated using linear regression methodology. Item difficulty indices were transformations of the familiar proportion-correct item score, obtained from data gathered during the spring of 1989 from 158 deaf examinees. Variation in the item difficulty values was substantially accounted for in terms of a small number of predictor variables (R2≥.90). Implications of the results for construct validity and interpretation of test scores are discussed.

The NTID speech recognition test: NSRT ®

Abstract Objective: The purpose of this study was to collect and analyse data necessary for expansion of the NSRT item pool and to evaluate the NSRT adaptive testing software. Design: Participants were administered pure-tone and speech recognition tests including W-22 and QuickSIN, as well as a set of 323 new NSRT items and NSRT adaptive tests in quiet and background noise. Performance on the adaptive tests was compared to pure-tone thresholds and performance on other speech recognition measures. The 323 new items were subjected to Rasch scaling analysis. Study sample: Seventy adults with mild to moderately severe hearing loss participated in this study. Their mean age was 62.4 years (sd = 20.8). Results: The 323 new NSRT items fit very well with the original item bank, enabling the item pool to be more than doubled in size. Data indicate high reliability coefficients for the NSRT and moderate correlations with pure-tone thresholds (PTA and HFPTA) and other speech recognition measures (W-22, QuickSIN, and SRT). Conclusion: The adaptive NSRT is an efficient and effective measure of speech recognition, providing valid and reliable information concerning respondents’ speech perception abilities.

A closed-set sentence protocol for assessing speech discrimination in deaf individuals: the speech sound pattern discrimination test

Forty hearing-impaired young adults were tested with a newly developed instrument designed to assess auditory speech processing skill. Analyses indicated that the resulting test data could be characterized in terms of the Rasch model for person measurement. Evidence of the scales empirical validity also was obtained. The instrument uses a closed-set sentence discrimination task, and appears to be useful over a fairly wide range of hearing losses.

Validity of the American Sign Language Discrimination Test

American Sign Language (ASL) is one of the most commonly taught languages in North America. Yet, few assessment instruments for ASL proficiency have been developed, none of which have adequately demonstrated validity. We propose that the American Sign Language Discrimination Test (ASL-DT), a recently developed measure of learners’ ability to discriminate phonological and morphophonological contrasts in ASL, provides an objective overall measure of ASL proficiency. In this study, the ASL-DT was administered to 194 participants at beginning, intermediate, and high levels of ASL proficiency, a subset of which (N = 57) also was administered the Sign Language Proficiency Interview (SLPI), a widely used subjective proficiency measure. Using Rasch analysis to model ASL-DT item difficulty and person ability, we tested the ability of the ASL-DT Rasch measure to detect participant proficiency group mean differences and compared its discriminant performance to the SLPI ratings for classifying individuals into their pre-assigned proficiency groups using resource operating characteristic statistics. The ASL-DT Rasch measure outperformed the SLPI ratings, indicating that the ASL-DT may provide a valid objective measure of overall ASL proficiency. As such, the ASL-DT Rasch measure may provide a useful complement to measures such as the SLPI in comprehensive sign language assessment programs.

Applications of the NTID speech recognition test (NSRT

Abstract Objective: This study evaluated the diagnostic capabilities of an adaptive speech recognition protocol (NSRT®) that can be self-administered in non-clinical venues by listeners using internet-based software. Design: All participants were given an audiological evaluation, including pure-tone testing, and responded to the NSRT administered in quiet and + 5 dB SNR listening conditions. The NSRT test materials are sentence-length utterances containing phonetic contrasts, primarily minimal pairs. Study sample: Subjects were 123 adults with normal hearing to moderately severe sensorineural hearing loss (mean age = 55 years, SD = 23). Results: Performance on the NSRT is strongly related to pure-tone thresholds. Linear regression analyses support the utility of the NSRT as a proxy for clinically-obtained hearing thresholds across the octave frequencies 0.5 to 8 kHz, primarily for individuals in the − 10 to 55 dB HL range. Other NSRT results are linked to analyses of phonetic errors and components of aural rehabilitation. Conclusions: Among its numerous results, the NSRT yields quantitative predictions of frequency-specific hearing thresholds, provides insight into the phonetic errors that affect speech understanding in adults who suffer from sensorineural hearing loss, primarily in the − 10 to 55 dB HL range, and has implications for the design of individualized auditory training programs.