The Utility and Robustness of Sentence Repetition as a Marker of Developmental Language Disorder: An Analysis of SCALES Project Data

Purpose: This study examined the diagnostic power and robustness of sentence repetition (SR) in distinguishing monolingual English-speaking children with developmental language disorder (DLD) from typically developing (TD) children, using a large-scale secondary analysis of the Surrey Communication and Language in Education Study (SCALES) dataset (Norbury, 2022). We evaluated SR’s effectiveness across different scoring methods in age-matched groups across three different time-points.<br/><br/>Method: A total of 407 children were included. Bayesian beta regression models compared SR performance between groups across four scoring methods. SR’s diagnostic accuracy was assessed using area under the curve (AUC), sensitivity, specificity, and likelihood ratios.<br/><br/>Results: Children with DLD consistently performed less accurately than TD peers on SR tasks, with differences persisting across ages five to 11 and across all scoring methods. AUC values indicated good to excellent discriminative ability, especially in younger groups, though sensitivity and specificity fell below clinical thresholds.<br/><br/>Conclusions: These findings support SR’s diagnostic potential as a reliable language measure. SR may serve as a valuable tool due to its ease of use and scoring flexibility, though additional assessments are recommended for comprehensive language evaluation.