A Longitudinal Study of Spanish Language Growth and Loss in Young Spanish-English Bilingual Children.

This longitudinal study examined trajectories of Spanish language growth and loss in 34 Spanish-English bilingual children attending an English immersion school. Narrative retell language samples were collected in Spanish across 3 years using wordless, picture storybooks. Digital audio recordings were transcribed, coded, and analyzed for mean length of utterance in words, proportion of grammatical utterances, and moving-average type-token ratio. Code switching into English was also coded at the word level to determine its potential impact on moving-average type-token ratio. Growth curve models were used to estimate the change over time for each outcome measure. The findings indicated that the Spanish-English bilingual participants who attended an English immersion school demonstrated loss of Spanish grammatical and lexical production (as defined by encompassing maintenance and or significant deceleration) from preschool through kindergarten, and that the degree of loss in lexical production was impacted by whether code switching was included or excluded. The findings are discussed in the context of clinical decision-making when assessing the Spanish expressive language abilities of this specific population.