Does the effectiveness of a reading intervention differ dependent on students' Spanish or English proficiencies?

This study investigated whether linguistic proficiencies in students' first language (L1)— Spanish—and English (L2) moderated the response to intensive reading intervention for sixth- and seventh-grade multilingual learners (MLs) with reading difficulties. We used confirmatory factor analysis to estimate proficiency scores in English and Spanish using measures of expressive and receptive vocabulary, syntax, and grammar. We then used latent variable moderated structural equation modeling to evaluate how proficiency in English and Spanish moderated the effect of treatment on students' reading outcomes in response to intervention. Two important findings occurred. First, the overall linguistic proficiencies of the sample were below average, suggesting the prevalence of low L1 and L2 may be high among the population of middle gradeMLs with reading difficulties. Second, we observed only one significant moderation effect: the effect of treatment on students' letter and word recognition was statistically significantly higher for students with higher English proficiency.