Abstract
Background : Socially disadvantaged children are more likely than their advantaged peers to have delayed language development. Parent talk to children has been found to be related to child language abilities and to socioeconomic status. Based on an interactionist theory of language development, it is proposed that child language may be supported, in part, by encouraging parents to talk to their baby. Speech and language therapy services in the UK have developed a range of preventative services to this end but there is little evidence of effectiveness. In this study, a randomised controlled trial (RCT) was carried out to investigate efficacy of the Babytalk Home Visit (BTHV) on parent talk to children and on child expressive vocabulary. Method: 69 parent/baby dyads were randomised to BTHV and control groups, videoed and parent talk transcribed in their homes at baseline, post intervention and when their child was aged 2 years. Baseline to post-intervention change in parent word types spoken and parent report of child expressive vocabulary at age 2 years were compared between groups. Results: No significant difference was observed between groups for either outcome measure. Subgroup analysis indicated a possible temporary effect on parental talk for parents from low socioeconomic backgrounds. This effect was not sustained at the 2 year follow up, however, and no effect on child language outcomes at age 2 was observed. In line with previous studies, a highly significant relationship was found between parent talk and child language. Discussion: These results highlight the need to understand the potential and mechanism for change in parent talk and the need for further research into the nature of the relationship between parent talk and child language. They also highlight the value of controlled studies to inform commissioning of speech and language therapy services using the MRC’s guidance for complex interventions.