Revisiting the traditional conceptualizations of vocabulary knowledge as predictors of dual language learners' English reading achievement in a new destination state

The unprecedented growth of Spanish-English dual language learners (DLLs) in new destination states (e.g., Georgia, Indiana, South Carolina, Tennessee) calls for better understanding of the relation between their bilingual vocabulary skills and English reading achievement. The current study focused on school-age Spanish-English DLLs (N = 60) in Tennessee and explored how various vocabulary knowledge conceptualizations predict English reading comprehension achievement, controlling for English word reading skills and grade level. Vocabulary knowledge was assessed using monolingual (English-only and Spanish-only) and bilingual (conceptual and total) scoring methods. Results showed that, while DLLs performed below the national mean for English-only and Spanish-only vocabulary, they performed within the average to above-average range for bilingually scored conceptual vocabulary. More uniquely, the expressive vocabulary knowledge emerged as a robust predictor of English reading comprehension above and beyond the influence of English word reading skills. Findings suggest practical and theoretical value of bilingually driven vocabulary assessment approaches. As expected, bilingually scored vocabulary provided a more comprehensive understanding of DLLs' vocabulary knowledge by accounting for vocabulary knowledge in both Spanish and English, compared to monolingually scored vocabulary. We discuss theoretical and instructional implications, with a focus on asset-driven and scientific assessment understandings for supporting DLLs' vocabulary and reading achievement in new destination states.