Validation of the Manchester spoken language development scale (MSLDS)

Introduction: Standardized outcome measures are importantfor accurately monitoring the language development of pre-lingually deaf children receiving auditory implants. Current commonly used outcome measures are time-consuming,limiting the practicality of regular testing. To address these limitations, the Manchester Spoken Language Development Scale (MSLDS) was developed as a quick and easily applicable interim measurement. This is an 11-point scale designed to provide a streamlined overview of a child's expressive language development. This study describes the MSLDS, evaluates its ease of use and inter-rater reliability, and outlines its application in the paediatric auditory implant population. Methods: Sixteen speech therapists and teachers for the deaf reviewed videos of paediatric cochlear implant assessmentsand rehabilitation sessions at a UK auditory implant centre. Twenty-five videos from fourteen children were used in this validation study. Reviewers were asked to evaluate a child's language development using the MSLDS by assigning a score for each video and to evaluate the ease of use of the scale. Each video wasrated by three different reviewers. Results: MSLDS scores showed a high degree of consistency between raters for each child. 8/25 (32%) videos demonstrated perfect agreement on the MSLDS. In 15/25 (60%) videos, there was a one-point difference between MSLDS scores. The remaining 2/25 (8%) videos varied by 2 points. Statistical analysis demonstrated an intra-class correlation coefficient (ICC) of 0.987, indicating a high level of agreement between users of the scale. Qualitative feedback from the raters suggested further modifications which have been incorporated into the scale. Conclusion: The high inter-rater agreement reflects the potential for the MSLDS to be a reliable tool for monitoring language development in the paediatric auditory implant population.