Clinical skills training for speech and language therapists: Using the evidence-base to treat speech sound disorders using electropalatography (EPG)

Speech sound disorders (SSD) affect a large proportion of children on Speech and Language Therapists (SLTs) caseloads. The impact on the child can be far reaching, disturbing both social and educational development. Traditional therapy interventions are often lengthy and do not always resolve the SSDs. Electropalatography (EPG) is an instrumental visual-feedback technique used mainly in research clinics which has proven effective in the treatment of SSDs. This research aimed to train six SLTs in the use of EPG to treat children for whom traditional methods had failed. Workshops were offered to all interested SLTs which targeted: increasing knowledge of SSDs and possible barriers to success in therapy; increasing knowledge of EPG, specifically diagnostic benefits and therapy outcomes; helping SLTs to identify children on their caseload who may benefit from EPG. Following these 28 children were referred for consideration from which 3 children were chosen. Two of the three children responded to EPG therapy and successfully remediated their speech errors within 12 weeks and were subsequently discharged. For the third child who has multiple speech errors and requires ongoing surgical intervention in addition to therapy, EPG proved diagnostically very important as well as allowing progress previously not made in therapy. It became apparent that data security policies in NHS Lothian are incompatible with the Articulate Assistant software required to run EPG. Therefore whilst this method of intervention proved very successful in remediating the SSDs it cannot currently be adopted into the NHS without further considerations. Alternative visual-feedback techniques are being explored. Wood & Gardiner (2016) Clinical Skills Training: Treating SSDs with EPG CASL Research Centre Working Paper WP-23 (2016) 2 1 Background Children with “speech sound disorders” (SSD) make up a considerable proportion of a Speech and Language Therapists (SLT) caseload which is estimated to be approximately 6.5% of all UK children. Current practice relies on SLTs using auditory perceptual judgements about a child’s speech difficulties to assess and diagnose the nature of the problem and rely on the child’s own auditory perceptual abilities when listening to the therapist’s and their own speech productions. SLTs are very skilled at describing and highlighting speech errors to young children and many children will be able to resolve their speech difficulties. However, for some this is a slow process, taking many hours of SLT time and for others correct productions are never achieved. This can negatively impact on education, social development and self esteem. 1.1 Electropalatography Electropalatography (EPG) is a long established tool for clinical and non-clinical research. It can provide unique diagnostic data and be used in real-time as a computer based biomedical feedback technique. Together, these properties have been found to be effective in treating articulation disorders that have failed to respond to conventional therapy approaches [1,2,3,4]. EPG records timing and location of tongue contacts with the hard palate during speech and registers characteristic patterns for many consonants in English. It requires the individual to have a custom-made artificial palate (figure 1) which fits against the roof of the mouth. Embedded into the artificial palate are 62 electrodes that register on a computer screen when the tongue is touching them. An individual’s articulation can be compared to standard patterns for English consonants (see figure 2) and error patterns noted. EPG is a particularly valuable diagnostic tool in a clinical setting because it gives objective and detailed analysis of the child’s articulation patterns and may identify errors which cannot be detected by perceptual analysis alone yet are vital for accurate diagnosis and subsequent effective intervention [5]. t, d, n k, g, ng s, z sh Figure 2. Standard articulatory patterns Figure 1. EPG palate Wood & Gardiner (2016) Clinical Skills Training: Treating SSDs with EPG CASL Research Centre Working Paper WP-23 (2016) 3 EPG can also be used to modify articulatory patterns by using visual feedback. The speech and language therapist (SLT) selects a target articulation pattern characteristic of a particular sound which is currently incorrectly produced and demonstrates what the sound looks like through use of diagrams (figure 2) or a live demonstration on the computer. During therapy the child attempts to copy this correct articulation by visually monitoring their own contact patterns in real time. A portable training unit (PTU figure 3), can be used in therapy instead of the full clinic-based recording and analysis system and can be sent home with the child for additional practice. Figure 3. A Portable Training Unit (PTU) used for home practice with parental/carer guidance. There is good evidence that EPG is an effective form of therapy and it been suggested that EPG therapy may expedite results [6]. However EPG remains a specialised technique not routinely used in clinical practice. 1.2 Aims NHS Lothian has a full EPG system but due to a change in therapists over several years current SLTs are not trained to use it. Therefore the project aimed to: 1. Offer specialist workshops in speech sound disorders to all NHS Lothian SLTs to enable them to identify which children may benefit from EPG therapy 2. Train a subset of SLTs in the use of EPG for assessment and treatment of children with intractable speech sound disorders 3. Evaluate the use of EPG as a clinical non-research centre tool 4. Contribute directly to evidence-based practice 5. Establish collaborative links between NHS and QMU Wood & Gardiner (2016) Clinical Skills Training: Treating SSDs with EPG CASL Research Centre Working Paper WP-23 (2016) 4 2 Methods Three specialist workshops in SSDs were offered to all SLTs across Edinburgh and the Lothians in June 2013. These workshops were aimed at: increasing SLT knowledge of SSD and possible barriers to success in therapy; increasing SLT knowledge about EPG, its diagnostic benefits and use in remediation of SSDs; helping therapists to identify children on their caseload who would benefit from EPG therapy. Following these workshops, SLTs in NHS Lothian identified children who they felt may benefit from EPG intervention and details of these children were referred to the Clinical Lead in Speech Sound Disorders. Twenty-eight cases were referred. Each was considered and a short list of eight was identified for consideration. All eight children were visited by Wood and three boys, aged between 9 and 15 years, were selected (P1, P2, and P3). The boys all presented with persistent difficulties in the production of /k/ and /g/, usually be acquired by age 3 years, despite significant amounts of intervention prior to this study. Six therapists, two each from West Lothian, East / mid Lothian and Edinburgh city were identified to undergo specific EPG training which targeted: demonstration and supervision of EPG assessment; identification of speech production errors; selecting appropriate targets for intervention; devising, structuring and delivering EPG therapy sessions; monitoring clinical outcomes.