Validation of the Intelligibility in Context Scale for Korean-speaking pre-school children

Purpose: The Intelligibility in Context Scale (ICS) is a parent-reported screening tool focussed on parents' perception of their child's speech intelligibility. The purposes of this study were to evaluate the psychometric properties of the Korean version of the ICS (ICS-K) and to investigate whether the ICS-K is a useful tool for distinguishing between Korean-speaking children with typical development (TD) and those with speech sound disorder (SSD). Method: A total of 178 Korean-speaking pre-school children (145 children with TD and 33 children with SSD) participated in this study. Speech skills were assessed using the Assessment of Phonology and Articulation for Children. The parents of the children completed the ICS-K. Result: The ICS-K showed high internal consistency and test-retest reliability. Criterion validity was established through a significant correlation between the ICS-K and the percentage of consonants correct. Construct validity was also established through significant correlations between the ICS-K mean scores and the item scores. A discriminant analysis revealed that the ICS-K had high sensitivity (90.9%) and adequate specificity (77.9%) in classifying children into either the TD or the SSD group. Conclusion: The psychometric properties of the ICS-K support its clinical value in measuring functional speech intelligibility in Korean-speaking children with SSD.