Using the Quantifying Bilingual Language Experience Questionnaire to Identify Risk for Language Impairment in Bilingual Children

Purpose: Clinical triage, but also inclusive population sampling in research, requires efficient detection of children likely to be at risk for language impairment (LI), a signif icant challenge in the case of bilingual children. Our goal was to derive automatic risk factor indices from a parental questionnaire and compare their usefulness in ini tial identification of children at risk for LI. Method: Alternative risk factor indices were derived from the Quantifying Bilingual Language Experience (Q-BEx) online questionnaire backend calculator, differing in the weight and detail given to language proficiency. Each index was applied to two data sets composed of 5- to 8-year-old children: one with independent diagnosis of developmental language disorder (DLD)/typical development (TD; 109 bilingual children tested in France) and one of largely all-comer children (278 bilingual and monolingual children tested in France, the Netherlands, and the United Kingdom). We compared how these alternative indices predicted (likely) DLD/TD status and structural language outcomes, assessed with Language Impairment Testing in Mul tilingual Settings tools, designed for bilingual children. Results: RF4-min, a risk factor index composed of four equally weighted compo nents (age of first word, age of first sentence, early development concerns, and strongest speaking skills between the home/heritage language and the societal language), satisfactorily separated bilingual children according to developmental status and was a significant predictor of language outcomes. This composite score showed the best balance between separability, sensitivity, and predictive value compared to indices without a proficiency component or with a more heavily weighted/detailed proficiency component. Conclusion: RF4-min, a Q-BEx automatically derived composite risk factor index, yielded promising results, indicating usefulness as part of first-level triage for LI.