Two Measures, Same Outcome: Comparable Associations Between Exposure Measurements and Language Performance in Bilinguals With and Without Developmental Language Disorder

PURPOSE: Language exposure is associated with language performance in bilinguals. Two common ways of measuring language exposure are total hours of exposure and percentage of exposure. This study compared differences in these two methods and examined their associations with bilingual language performance. Differences between typically developing (TD) children and those with developmental language disorder (DLD) were also analyzed across exposure measures and language performance. METHOD: Participants were 1,397 Spanish-English bilingual preschool children (73 identified with DLD). Caregivers reported hour-by-hour language input and output for a typical weekday and a typical weekend. Children's bilingual language performance was measured using a standardized language screener. Correlation and effect size analyses were calculated. RESULTS: Percentage and total hours of exposure were strongly and significantly correlated for both Spanish and English. Both measures showed moderate, significant correlations with bilingual language performance, with minimal differences in effect sizes. Significant group differences emerged between TD and DLD children, with small-to-medium effect sizes. The DLD group showed significantly weaker correlations between language exposure measures and language performance compared to the TD group. CONCLUSIONS: The results indicate that both measurement methods are statistically comparable, suggesting that clinicians may use either method to assess language exposure in bilinguals. The weaker correlations observed in the DLD group imply that additional factors beyond exposure influence their bilingual language performance and should be considered in evaluation. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.34024479.