Evidence based pathways to intervention for children with language disorders

Background: Paediatric SLT roles often involve planning individualised intervention for specific children (provided directly by SLTs or indirectly through non-SLTs), working collaboratively with families and education staff and providing advice and training. A tiered approach to service delivery is currently recommended, whereby services become increasingly specialised and individualised for children with greater needs.

Aims: To examine 1) evidence of intervention effectiveness for children with language disorders at different tiers and 2) evidence regarding SLT roles; and to propose an evidence-based model of SLT service delivery.

Methods: Controlled, peer-reviewed studies, meta-analyses and systematic reviews of interventions for children with language disorders are reviewed and their outcomes discussed, alongside the differing roles SLTs play in these interventions. We indicate where gaps in the evidence base exist and present a possible model of service delivery consistent with current evidence, and a flowchart to aid clinical decision making.

Main Contribution: The service delivery model presented resembles the tiered model commonly used in education services, but divides individualised (Tier 3) services into Tier3A: indirect intervention delivered by non-SLTs, and Tier 3B: direct intervention by an SLT. We report the evidence for intervention effectiveness and which children might best be served by each tier, the role SLTs could take within each, and the evidence of effectiveness of these roles. Regarding universal interventions provided to all children (Tier 1) and those targeted at children with language weaknesses (Tier 2), there is growing evidence that approaches led by education services can be effective when staff are highly trained and well-supported. There is currently limited evidence regarding additional benefit of SLT-specific roles at Tiers 1 and 2. With regard to individualised intervention (Tier 3): children with complex or pervasive language disorders progress significantly following direct individualised intervention (Tier 3B), whereas children with milder or less pervasive difficulties can make progress when intervention is managed by an SLT, but delivered indirectly by others (Tier 3A), provided they are well-trained, -supported and -monitored.

Conclusions: SLTs have a contribution to make at all tiers, but where prioritisation for clinical services is a necessity, we need to establish the benefits and cost-effectiveness of each contribution. Good evidence exists for SLTs delivering direct individualised intervention, and we should ensure that this is available to those children with pervasive and/or complex language impairments. In cases where service models are being provided which lack evidence, we strongly recommend that SLTs investigate the effectiveness of their approaches.