Factors affecting communication outcomes for deaf and multilingual learners: A systematic review.

Background: Deaf and hard-of-hearing (DHH) children who are exposed to more than one spoken language can be described as deaf and multilingual learners (DMLs). Increased globalization and technological advancements in hearing amplification mean an increasing number of children who are DHH access more than one spoken language (with and without the presence of signed languages). A growing body of evidence suggests that DMLs can develop competency in more than one spoken language. However, critical evaluation of factors contributing to positive outcomes appears limited.
Aims: The purpose of this systematic review was to identify factors that facilitate and inhibit the development of listening, speech, and language skills in more than one spoken language for DMLs.
Methods: Following PRISMA guidelines, searches of seven databases were conducted. Methodological quality of the studies used the Quality Assessment with Diverse Studies (QuADS) tool. Seventeen studies met the inclusion criteria. All studies measured outcomes in a home language and the majority community language. Forty two different outcome measurement/assessment tools were used, making comparison across the studies difficult.
Main Contribution: A range of factors emerged from the interventions, which supported or inhibited the outcomes for DMLs. The results of this review provide insights for practitioners working with DMLs into the factors that promote spoken multilingual language learning and factors that limit positive listening, speech, and language outcomes. The results also contribute to recommendations for researchers to enable the multilingual outcome measurement for DML studies.
Conclusions: The listening, speech, and language outcomes of DMLs are enhanced through interventions in each of the spoken languages to which the child is exposed. This is facilitated by increased engagement of parents who are encouraged to maintain their home language. Furthermore, culturally inclusive practices promote multilingual language development in DMLs and should be included in informing policy decision-making.