Purpose: The purpose of this investigation was to compare the efficiency of dialogic reading strategies (DRS) provided bilingually (Spanish and English) and solely in English on the acquisition of vocabulary of young school-aged dual-language learners (DLLs) with developmental language delayrs (DLD). Method: Five participants between the ages of 5 and 8, identified with or suspected of having a DLD, participated in this adapted alternating treatment design investigation. The primary dependent variable (DV) was English vocabulary naming, and the secondary DV was Spanish vocabulary naming. Participants received 5 weeks of shared book reading with DRS intervention alternatively in English only and bilingually, either individually or in a small-group format. Results: Each participant exhibited a noticeable increase in English vocabulary naming after introducing both treatment conditions. However, the bilingual rendition of DRS was more efficient because all five participants learned not only English words (L2) but also Spanish (L1) vocabulary during the intervention. Conclusion: This investigation provided evidence that a bilingual approach to DRS is a practical and efficient way to increase vocabulary in both L1 and L2 when used to treat young school-aged DLLs with DLD. Further research is needed to examine the effects of this intervention in Spanish-speaking DLLs who present a broaders range of linguistic and academic needs, as is the case of students in special education self-contained classes.
