Using latent profiles to evaluate response to a language-based intervention.

Many children with oral language difficulties also experience challenges with word reading, as evidenced in the high comorbidity rate between developmental language disorders and dyslexia. The current study investigated a sample of students (n = 357) with language and literacy difficulties classified into latent classes based on pre-intervention performance on word reading and listening comprehension measures. Specifically, this study sought to determine the extent to which latent classes responded to an evidence-based, narrative language program at immediate post-test and a five-month follow-up time point, and whether performance varied as a function of class membership. Findings revealed that students in all latent profiles showed statistically significant improvements in narrative language at post-test, a primary target of the intervention. However, intervention effects varied at a five-month follow-up time point, with students with the greatest listening comprehension and word reading difficulties showing the most notable gains. Instructional response also varied according to performance on a narrative writing measure. These findings suggest that assessing initial performance on key variables may be able to help educators predict student response and adapt intervention plans to more effectively meet individual needs.