Oral Language Skills Intervention in Pre-school – A Cautionary Tale

Background: While practitioners are increasingly asked to be mindful of the evidence-base of intervention programmes, evidence from rigorous trials for the effectiveness of interventions that promote oral language abilities in the early years is sparse.

Aims: This study evaluates the effectiveness of a language intervention programme for children identified as having poor oral language skills in preschool classes.

Methods & Procedures: A randomised controlled trial was carried out in 13 UK nursery schools. In each nursery, eight children (N = 104, mean age = 3 years 11 months) with the poorest performance on standardised language measures were selected to take part. All but one child was randomly allocated to either an intervention (N = 52) or a waiting control group (N = 51). The intervention group received a 15-week oral language programme in addition to their standard nursery curriculum. The programme was delivered by trained teaching assistants and aimed to foster vocabulary knowledge, narrative and listening skills.

Outcomes & Results: Initial results revealed significant differences between the intervention and control group on measures of taught vocabulary. No group differences were found on any standardised language measure; however there were gains of moderate effect size in listening comprehension.

Conclusions & Implications: The study suggests that an intervention, of moderate duration and intensity, for small groups of preschool children successfully builds vocabulary knowledge, but does not generalize to non-taught areas of language. The findings strike a note of caution about implementing language interventions of moderate duration in preschool settings. The findings also highlight the importance of including a control group in intervention studies.