Development of Singapore English speech audiometry test materials

Abstract

Background Speech audiometry is utilised for diagnostic and rehabilitative purposes. Speech audiometry involves materials linguistic in nature. The ideal protocol is to have a tester who is a native or at least a fluent speaker of that language to conduct the test on a native listener. Except for a set of psychometrically equivalent word recordings that have yet to be validated, no other existing speech audiometry materials have been developed in Singapore English. Objective This study aims to develop and validate a local set of phonemically balanced English word lists for use on Singaporeans. Methods The first phase encompassed the development of spondaic and phonemically-balanced monosyllabic word lists for Speech Reception Threshold (SRT) and Word Recognition Score (WRS) testing. The second phase established perceptual equivalence across the monosyllabic word lists. The third phase encompassed the validation of these materials on 72 normal-hearing and hearing-impaired Singaporeans between 21 to 80 years old. Participants were tested with two spondaic and six monosyllabic word lists. Participants’ SRT and WRS values were analysed. Results The mean SRT and pure tone audiometry (PTA) average difference was 5.79 dB. All 43 normal-hearing participants achieved a maximum WRS of 100%, at an average presentation level of 28.1 dB above their PTA average. Test-retest analysis revealed clinically insignificant differences across all word lists. Conclusion The test materials are validated to be suitable for testing on Singaporean English speakers. Normative SRT and WRS data for Singaporeans have also been established.