The ASCEND Study: Protocol for a Feasibility Study to Evaluate an Early Social Communication Intervention for Young Children with Down Syndrome

Background: Down syndrome is the most common cause of learning disability, affecting approximately 1 in every 700 babies. Children with Down Syndrome have particular difficulties with speech and language. This makes it challenging for them to participate fully in life, access health care services and educational opportunities. Improving the language skills of young children with Down Syndrome is vital for their future social and emotional well-being and behaviour, and consequently contribution to society. As Down Syndrome is detected before or at birth, we can provide support from early on. There are currently no standard interventions for improving the language skills of children with Down Syndrome under the age of 36 months. Evidence suggests that early parent-based interventions may be effective in improving language outcomes. In partnership with parents and speech and language therapists, we have co-developed an intervention focusing on early social communication skills and our preliminary work shows that it can lead to better language in children with Down Syndrome. Our aim is to carry out a feasibility study which will inform a future pilot/full trial to test whether the intervention is effective in improving language skills before children with Down Syndrome start school. Methods: This is a two-arm feasibility randomised controlled trial (RCT), with 1:1 randomisation stratified by trial site comparing the intervention (plus standard NHS speech and language therapy) with no intervention (standard NHS speech and language therapy only). We aim to recruit between 25 and 30 children with Down Syndrome aged between 12 and 30 months. Sites are defined by the geographical boundaries of three National Health Service (NHS) Trusts. Recruitment is from NHS Speech and Language Therapist caseloads within the 3 Trusts and self-referral. In the intervention arm parents/guardians will receive brief training on the parent-based intervention and a manual to follow with their child for 10 weeks. The children’s language and early communication skills and family health outcomes will be assessed by a blinded assessor at baseline, post-intervention and 6 month follow up. Questionnaire and semi-structured interviews will explore the acceptability of the intervention to parents and SLTs.Discussion: The feasibility study’s outcomes will determine whether it would be viable to progress to a full-trial and whether adjustments need to made to the procedures, data collection methods, intervention delivery, and the intensity of support needed. We want to assess whether our early intervention can be delivered and rolled out through NHS Speech and Language Therapy Services. We anticipate that NHS services will need to make ongoing changes due to the COVID19 pandemic, so it is likely we will need to make adjustments for the definitive trial. We will also calculate descriptive statistics of the language outcome measure which will we use for any future sample size calculation. Trial registration: ISRCTN13902755. Registered on 25th August 2020. http://www.isrctn.com/ISRCTN13902755