Abstract
Objective: The studies described in this article outline the design and development of a British English version of the coordinate response measure (CRM) speech-in-noise (SiN) test. Our interest in the CRM is as a SiN test with high face validity for occupational auditory fitness for duty (AFFD) assessment. Design: Study 1 used the method of constant stimuli to measure and adjust the psychometric functions of each target word, producing a speech corpus with equal intelligibility. After ensuring all the target words had similar intelligibility, for Studies 2 and 3, the CRM was presented in an adaptive procedure in stationary speech-spectrum noise to measure speech reception thresholds and evaluate the test–retest reliability of the CRM SiN test. Study sample: Studies 1 (n = 20) and 2 (n = 30) were completed by normal-hearing civilians. Study 3 (n = 22) was completed by hearing impaired military personnel. Results: The results display good test–retest reliability (95% confidence interval (CI) < 2.1 dB) and concurrent validity when compared to the triple-digit test (r ≤ 0.65), and the CRM is sensitive to hearing impairment. Conclusion: The British English CRM using stationary speech-spectrum noise is a “ready to use” SiN test, suitable for investigation as an AFFD assessment tool for military personnel.
Acknowledgements
Authors thank the Surgeon General of the Ministry of Defence for funding this work and to the military personnel and civilian participants.
Declaration of interest
No potential conflict of interest was reported by the authors.