An investigation into the efficacy of Speech Perception Assessments (SPAs) used by Speech and Language Therapists with the deaf paediatric population in the UK

Abstract

Predicted and actual speech and language development outcomes for deaf children are often at odds with one another (Clopper & Pisoni, 2006). As audiological assessments are poor predictors of speech processing and language development (Wood, 2002), Speech Perception Assessments (SPAs) were developed to provide more specific information regarding children’s access to spoken language. Concern that existing SPAs lack the specificity required by Speech & Language Therapists (SLTs) (DesJardin et al., 2009) has prompted SLTs to develop informal assessments (Limbrick et al., 2013). This research investigates the development, format, results and perceived efficacy of three SPAs: the Manchester Junior Word Lists (MJWL), Manchester Picture Test (MPT) and the Wales (Hearing Impairment) Speech Perception Assessment (WHISPA), an informal SPA developed by the author. Two studies were undertaken. Study 1 investigated the validity and reliability of the WHISPA test materials. Three test administrators undertook WHISPA with 26 English-speaking, typically developing children aged 3;0 - 5;0. Following amendments, WHISPA test materials were deemed suitable for use with children aged 3;0 and above. In Study 2, 17 SLTs administered the three SPAs to 45 deaf children from England and Wales, aged 5;0 – 11;4. The SLTs’ opinions of the SPAs were solicited through questionnaires and a focus group. Results indicate that WHISPA provides the specificity required by SLTs and II has greater validity and reliability than MJWL and MPT. MJWL and WHISPA identified speech perception difficulties in the same children, and high error rates in MJWL may indicate higher level processing difficulties. MPT lacked sensitivity, only identifying children with the most severe speech perception difficulties. SLTs preferred closed-set SPAs which required no verbal response, the quick administration of MPT and the identification of acoustic-phonetic perception ability provided by WHISPA. Sample size, the method of classifying participants and SPA inclusion criteria may constrain the application of some results.