Parent-delivered early language intervention for children with Down syndrome: a feasibility randomized controlled trial

Abstract Background Children with Down syndrome experience significant language difficulties which impact a wide range of outcomes. Parents are well-placed to support their child’s language development but evidence-based interventions are limited. The primary objective of this feasibility randomised controlled trial was to evaluate the feasibility (recruitment, retention and adherence to intervention) of a parent delivered language intervention for young children with Down syndrome. Methods Thirty families with a child with Down syndrome (aged 3–6 years) living in North-West and South-East England, UK, were randomly allocated to an intervention (delivering language intervention for 20 min a day, 5 days a week, over 30 weeks) or to a waiting control group. Assessments were completed before intervention ( t0 ), immediately after intervention ( t1 ), and 4 months after intervention ( t2 ). The main outcome measures were descriptions of feasibility regarding recruitment and retention, and intervention completion. Acceptability of the programme and trial procedures were also examined. Exploratory outcomes (including researcher-delivered assessments blind to group allocation) addressed effects on children’s skills (language, executive function, early literacy); parents (knowledge, skills and confidence, well-being, quality of life); and the home learning environment. Results Expressions of interest were received from 81 families, 31 of whom completed screening. Thirty families met criteria for taking part and were randomised to intervention ( n = 15) or waiting control group ( n = 15). At post-test ( t1 ) and follow up ( t2 ), 27/30 families (90%) completed assessments. Families in the intervention group completed an average of 25 weeks of the 30-week programme with 10 families delivering > 145/150 sessions. These findings met a priori criteria for recruitment, retention, and adherence success. The intervention and trial procedures were positively evaluated by parents. Effects on exploratory outcomes were highly variable across measures (Hedges’ g = − 1.64 to 1.07). There were no adverse events related to study participation. Conclusions The trial was feasible to deliver and findings support progression to a definitive trial to evaluate programme effectiveness. Implications for outcomes and measures for the future definitive trial are discussed. Trial registration ISRCTN63251282.