Exploring Assumptions of the Bilingual Delay in Children With and Without Developmental Language Disorder

Purpose: Bilingual children are both over-and under-identified with develop-mental language disorder (DLD). We propose that this may be a function of monolingual approaches that fail to consider the dynamic nature of bilingualism as well as assumptions of bilingual delay. We explored the extent to which bilin-gual children with and without DLD demonstrated mixed dominance as a func-tion of exposure to English. We document patterns of performance in bilingual children with and without DLD on the Bilingual English-Spanish Assessment or Bilingual English-Spanish Assessment-Middle Extension in Spanish, English, and their best language scores. Method: A total of 595 (100 with DLD) Spanish-English bilingual children between the ages of 5 and 12 years were included in the analyses. We employed logistic regression to evaluate the probability of demonstrating mixed dominance across semantics and morphosyntax in Spanish and English by abil-ity status. We then evaluated the association between English exposure and performance in Spanish, English, and the best language on semantics and mor-phosyntax measures.Results: There were similar typically developing and DLD probabilities of Span-ish or English dominance associated with high degrees of Spanish and English exposure. Mixed dominance was associated with both ability and exposure. Children with DLD demonstrated more mixed dominance from 0% to 60% English exposure. The patterns of mixed dominance were similar by ability when they had more than 60% exposure to English. There were significant associa-tions between single language testing in Spanish and English with percentage of exposure for children with and without DLD. When the best score (comparing English and Spanish) was used, there were no significant associations with exposure for semantics or morphosyntax.Conclusions: These results inform researchers and clinicians about the nature of bilingual proficiency in children with and without DLD. Mixed dominance was observed in both groups but with different patterns at lower levels of English exposure in children with and without DLD. We also see that when children's best score is considered, all differences in performance along the bilingual con-tinuum are related to ability not language exposure. This has implications for how to consider children's language test scores in making clinical decisions about bilingual children.