A Randomized Cross-over Trial Examining the Efficacy of Implementing a Speech-generating Device for Rare Genetic Conditions

In Australia, a disease is considered rare if it affects less than 1 in 2,000 individuals. There are over 7,000 rare genetic conditions, with three quarters affecting children. Rare diseases are often serious and progressive, presenting with ongoing health and developmental challenges, including speech and language disorders.

Augmentative and alternative communication (AAC) is one of the ways to support children with little speech and children with rare genetic conditions should have access to such tools as early as possible to maximise learning opportunities. However, the efficacy of high-tech AAC methods, such as speech generating devices, for children with rare genetic conditions have not been rigorously examined.

In this randomised cross-over trial, 38 participants with a rare genetic condition will be randomised into two groups (n=19 per group), which will determine the sequence of treatment delivery. The primary aim of this trial is to evaluate the efficacy of implementing a speech-generating device on communication outcomes compared with their usual care (i.e. no device). Change in communication will be measured using a patient-defined outcome - this outcome is a 'communicative act' chosen at the beginning of the trial with participants and their family. This means that each participant will have an individualised communication outcome which will be targeted during treatment sessions and measured in assessment sessions. The secondary aims include parent-reported communication, family impact and language/communication competence.

Each participant will complete screening, preference testing and baseline assessments about 2-4 weeks before randomisation. Further assessments will be completed before and after each phase. For each participant, the change in assessment scores between the start and the end of each period will be calculated. The mean difference in the change in total score between the two periods will then be calculated.

Each participant is expected to be involved in the study for 12 weeks after randomisation. This is split into two phases (6 weeks each). In the treatment (device) phase, each participant will receive two 1-hour therapy sessions per week, for 6 weeks, with a communication device (or 12 x 1-hour therapy within a 6-week treatment phase). The device is implemented by a qualified speech pathologist on the project team and can occur at Murdoch Children's Research Institute or at the participants' home.