Addressing clinician-client mismatch: a preliminary intervention study with a bilingual Vietnamese-English preschooler.

Purpose: This project examined receptive vocabulary treatment outcomes in the two languages of a bilingual preschooler with moderate to severe language impairment.
Method: A series of single-subject experimental designs was used to compare English-only (EO) and bilingual (BI) approaches to receptive vocabulary treatment. The participant, Nam, was a boy age 3;11 (years;months) who was learning Vietnamese as a first language at home and English in his early childhood education program. Treatment was implemented by an EO interventionist using a computer interface and prerecorded audio files in Vietnamese and English. The dependent measure was the percentage of items that were correctly identified in each language.
Results: Combined studies revealed that the BI approach increased Nam's attention to task and was as effective as the EO approach for increasing his receptive vocabulary in English. Nam made vocabulary gains in both treatment conditions; receptive vocabulary gains were evident in both Vietnamese and English.
Conclusion: This project showed that it is feasible for an EO clinician to promote gains in both the home and school languages of a BI child through creative collaborations with BI colleagues and the use of technology. Replication with additional participants and treatment activities is needed to make further generalizations.