A study of the effect of a 30-week oral language intervention, delivered in the last 10 weeks of early care and education and continuing for 20 weeks through the transition to school, on children's initial language, narrative, phonological awareness, and literacy skills immediately after intervention completion and six months later, as well as an examination of the effect of the intervention on six-month reading comprehension as mediated by oral language abilities immediately after intervention completion, based on data from 180 children identified as having poorly developed language skills from 15 early care and education centers in England