ACQ Vol 13 no 3 2011

Table 4. Critically appraised article Article purpose An intervention study looking at whether children with delayed expressive vocabulary given dialogic book-reading intervention in two languages would gain words in both languages compared to a control group of similar children. They also wanted to measure if parents found this a satisfactory and appropriate intervention. The method had already been shown to be effective for monolingual children using similar presenting conditions and targets. Tsybina, I. & Eriks-Brophy, A. (2010). Bilingual dialogic book-reading intervention for preschoolers with slow expressive vocabulary development. Journal of Communication Disorders , 43 (6), 538–556. Randomly assigned to experimental and control groups. Control group had no intervention, but regular measures, during the intervention for the initial treatment group. The control group then had the treatment also. Level of evidence Level II-1 (Justice & Fey, 2004); NHMRC level – III-1. Participants 12 children, 22–42 months of age. The intervention Thirty x 15-minute sessions using dialogic book-reading strategies were provided in each language in the children’s homes, in English by the primary investigator and in Spanish by the children’s mothers, who were trained in the techniques of dialogic book-reading. The intervention took place over a 6-week period. Results The children in the intervention group learned significantly more target words in each language than the children in the control group. Effect sizes were large. The intervention children learned an average of 6.7 targets in English (range 5–9), and an average of 3.2 targets in Spanish (range 0–6). The control children learned an average of 0.8 targets in English (range of 0–1), and an average of 0.5 targets in Spanish (range 0–2). A post-test 6 weeks later showed the intervention children produced an average of 5.8 target words in English (range 2–9), and an average 2.3 targets in Spanish (range 0–7). Hence, gains were maintained, but not generalised. Post-intervention for both groups, there was no significant difference in attained scores (i.e., both groups learned similarly from the intervention). Mothers’ satisfaction ratings on a questionnaire ranged from 3.2–3.7 out of a maximum of 4. The children learned fewer Spanish than English words overall; however, there was a wide range. Those who learned the most Spanish targets were those children whose mothers used the most consistent Spanish input outside of the intervention sessions, based on information provided in the parent report on children’s language input. They were also mostly dual-parent families where both parents spoke Spanish, and had a higher maternal education level than the children who learned fewer Spanish words. Relatively small participant size, although very comparable with other intervention studies. Variability in participants in both presenting vocabulary sizes and degrees of exposure to each language. However, if gains were made regardless of these variabilities, the result is relatively robust. There was no monolingual comparison intervention; however, this would have required a much bigger group. The intervention utilised picture books, and wh- questions. This may not suit all children or mother’s styles or cultural expectations. Also, some parents may have provided many more than the minimum presentations of each item (3), whereas some may have only presented the required number. The study showed that children with slow expressive vocabulary development can make gains in two languages following intervention in two languages, compared to controls with no intervention. A relatively simple parent-based intervention was used, which was positively viewed by the parents concerned. Design Limitations Summary: Citation

research findings are now available, including work by Hoff and Place (in press), Pitko et al. (2007), and Paradis, Crago, Genesee, and Rice (2011) that have investigated the differences in language processing between bilingual and monolingual children. For instance, Hoff and Place (in press) reported on a longitudinal study of bilingual development based on data from 47 children (25 boys and 22 girls) exposed to both Spanish and English from birth and 56 children (30 boys and 26 girls) exposed only to English. The authors concluded that although bilingual children acquired (composite) vocabulary and syntax within the same range as monolingual children, the overall time taken to acquire their two languages was longer than the monolinguals’ one. This finding appeared strongly related to the relative amounts of input received in the two languages. Such findings support the need to look in detail at a child’s language history and input received during assessment, countering earlier arguments presented in this column to “treat all children the same” and “only consider English”. It is important to note in practice that a slightly different trajectory to language learning appears to be evident in bilingual children. Furthermore, the language skills of bilingual children may not be evenly distributed and special attention should be paid to the sociolinguistic contributions made by their different languages during assessment and intervention planning (Goldstein, 2006).

Table 5: Review articles identified Thordardottir, E. (2010). Towards evidence-based practice in language intervention for bilingual children.

indicating that children with language difficulties can learn two languages; 2) there are indications that two languages may be an advantage in language learning for some children; 3) participants in these studies represent a range of presenting conditions, including autism, Down syndrome, and hearing impairment, and all fail to support the idea that “it is too hard for these children to manage two languages”; and finally, 4) interventions can be successfully carried out using a variety of methods and do not require a bilingual SP in order to do so. Related evidence Given that there are still only a small number of studies investigating bilingual intervention for children with language disorders, it is important to consider other lines of supporting evidence. For example, we can look at what is known about normal bilingual acquisition, which suggests a potential advantage in bilingualism. A number of robust Kohnert, K. (2010). Bilingual children with primary language impairment: Issues, evidence and implications for clinical actions. Goldstein, B. A. P. (2006). Clinical implications of research on language development and disorders in bilingual children.

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ACQ Volume 13, Number 3 2011

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