Investigating the potential of a test of non-word discrimination as a screening tool for persisting speech sound difficulties

Background: Children with Speech Sound Disorders (SSDs) make up the largest client group for Speech Therapy services in Ireland and worldwide. Children with SSDs form a heterogeneous group and difficulties can be attributed to one or more of a number of possible underlying deficits. In order to best design and implement targeted and individualised treatment, more sensitive screening tools need to be developed that will aid in the prioritisation of caseloads and ensure children requiring clinician-directed intervention receive it Objectives: The potential of a new screening tool as a prognostic indicator will be examined. Methods: 11 children with SSD aged between 3;2 and 4;05 were recruited from waiting lists of local SLT clinics. At initial assessment, non-standardized tests of non-word discrimination and real-word discrimination were administered as well as the Diagnostic Evaluation of Articulation and Phonology (DEAP) (Dodd et al. 2002), a standardized test of phonology. Improvement in percentage of consonants correct (PCC) on the DEAP was measured again eight weeks later. Original scores on both NWD and RWD tests were compared to improvements in PCC. Results: The children who scored above threshold on the test of NWD also scored the highest in a test of RWD. These children also made the biggest improvement as measured by DEAP PCC over eight weeks compared with the children who scored below threshold on NWD. Conclusions: Findings are consistent with the theory that a test of NWD may be a more sensitive predictor of whether children’s phonological systems will improve without intervention than factors such as severity alone. Further research is needed with a larger sample size to see if results prove significant.