Evaluating the treatment effect of repeated probes

A systematic review and classification of interventions for speech-sound disorder in preschool children

BACKGROUND

Multiple interventions have been developed to address speech sound disorder (SSD) in children. Many of these have been evaluated but the evidence for these has not been considered within a model which categorizes types of intervention. The opportunity to carry out a systematic review of interventions for SSD arose as part of a larger scale study of interventions for primary speech and language impairment in preschool children.

AIMS

To review systematically the evidence for interventions for SSD in preschool children and to categorize them within a classification of interventions for SSD.

METHODS & PROCEDURES

Relevant search terms were used to identify intervention studies published up to 2012, with the following inclusion criteria: participants were aged between 2 years and 5 years, 11 months; they exhibited speech, language and communication needs; and a primary outcome measure of speech was used. Studies that met inclusion criteria were quality appraised using the single case experimental design (SCED) or PEDro-P, depending on their methodology. Those judged to be high quality were classified according to the primary focus of intervention.

OUTCOMES & RESULTS

The final review included 26 studies. Case series was the most common research design. Categorization to the classification system for interventions showed that cognitive-linguistic and production approaches to intervention were the most frequently reported. The highest graded evidence was for three studies within the auditory-perceptual and integrated categories.

CONCLUSIONS & IMPLICATIONS

The evidence for intervention for preschool children with SSD is focused on seven out of 11 subcategories of interventions. Although all the studies included in the review were good quality as defined by quality appraisal checklists, they mostly represented lower-graded evidence. Higher-graded studies are needed to understand clearly the strength of evidence for different interventions.

Evidence-based intervention for preschool children with primary speech and language impairments: Child Talk – an exploratory mixed-methods study

Background

The Child Talk study aimed to develop an evidence-based framework to support the decision-making of speech and language therapists (SLTs) as they design and plan interventions appropriate to the needs of individual children with primary speech and language impairments and their families. The need for early identification and effective intervention for these children continues to be a government policy priority because of the link between children’s early speech and language skills and their broader well-being and outcomes in later life. The first phase of Child Talk sought to map and describe current SLT practice for these children; identify and summarise the existing research evidence relating to practice; and investigate the perspectives of parents, early years practitioners, preschool children and ‘underserved’ communities on speech and language therapy. The second phase of Child Talk focused on the development of a toolkit – assessment tools, outcome measures and a data set – to support future service and economic evaluations of the framework.

Methods

Child Talk adopted a mixed-methods design. Quantitative methods included surveys and investigated the prevalence and patterns of intervention usage; qualitative data collection methods included focus groups, interviews and reflection to investigate participants’ perspectives and understandings of interventions. Data analysis methods included descriptive and inferential statistics, thematic and content analysis and framework analysis. Participants were recruited nationally through six NHS sites, professional bodies, parent groups and advertising. Participants included SLTs (n = 677), parents (n = 84), preschool children (n = 24), early years practitioners (n = 31) and ‘underserved’ communities (n = 52).

Key findings

Speech and language therapy interventions were characterised in terms of nine themes, viewed as comprehensive and inclusive by practitioners. Relevant assessments, interventions and outcome domains were identified for the nine themes. Areas of tacit knowledge and underspecified processes contributed to variability in the detail of the framework. Systematic reviews identified 58 relevant and robust studies (from 55,271 papers retrieved from the initial literature search). The number of studies relevant to each theme varied from 1 to 33. Observational data on preschool children’s perspectives on speech and language therapy interventions revealed the dynamic nature of their interaction with different activities and people within therapy sessions. Parents’ experiences of speech and language therapy were generally positive although some reported that the rationale for therapy was not always clear. Parental perspectives in underserved communities suggested that, although parents were confident about how to support children’s language development, they were less informed about the nature of language impairments and the function of speech and language therapy. The availability of information regarding resources directed towards speech and language therapy services was poor. In particular, services lacked both a culture of collecting outcome data routinely and measures of professional input and costs associated with their activities.

Conclusion

A descriptive framework of SLT practice has been developed to support the discussions between therapists and families when making decisions regarding the selection of interventions and outcome measures. Further research is needed to address gaps in the intervention framework and evaluate its effectiveness and cost-effectiveness in improving outcomes for preschool children with primary speech and language impairments.

Study registration

This study is registered as PROSPERO CRD42013006369.

Funding

The National Institute for Health Research Programme Grants for Applied Research programme.

Treatment efficacy: functional phonological disorders in children

This report addresses the efficacy of treatment for functional phonological disorders in children. The definition of phonological disorders and their incidence and prevalence are first presented. The impact of this disorder on the lives of children and the role that speech-language pathologists play in treating this disorder are then discussed. Evidence of the positive outcome of phonological treatment is reviewed, with particular emphasis on treatment procedures that have been deemed effective, the specific effects of these treatments on improving intelligibility, and comparisons between treatments in facilitating improved sound production.

Teaching and learning /θ/: A non-confound

The purpose of this study was to replicate and extend the findings on the effectiveness of homonymous versus non-homonymous treatment approaches for children with phonological disorders, following Gierut (1991b). The present study was motivated by a potential confound noted in the previous report; namely, the specific sounds /θ, θ/ treated in the presumably less effective homonymous condition may have inhibited degree of phonological change. It was thus necessary to teach these more difficult, late-acquired interdental fricatives in the more effective non-homonymous treatment condition using identical methods and procedures. Results indicated that a non-homonymous teaching approach again motivated greater phonological change than a homonymous approach, regardless of sounds that were taught. These findings have implications for the independence of linguistic structures of treatment in inducing sound change, and bear upon assumptions about ease of sound learning based on normative developmental sequences.