Case Study 1: An Evidence-Based Practice Review Report. Theme: Interventions for children with Special Educational Needs

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1 Case Study 1: An Evidence-Based Practice Review Report Theme: Interventions for children with Special Educational Needs Are class-based oral language interventions effective in improving language skills in children with Speech, Language and Communication Needs? Summary A systematic literature review was carried out to evaluate class-based interventions for children with Speech Language and Communication Needs (SLCN). This is a model that is increasingly being used in the UK to provide speech and language therapy to children with SLCN. Class-based interventions refer to those delivered by school staff (usually a teacher or teaching assistant), with support from a Speech and Language Therapist. This model can also be referred to as indirect therapy or the consultation model of speech and language therapy. The review evaluates five studies that investigated class based interventions for children with SLCN. Studies were evaluated using Gough s (2007) weight of evidence framework; three were assigned a low rating, and two achieved medium ratings. The studies assessed the impact of the language intervention on various measures including receptive language, expressive language, vocabulary, grammar and narrative skills. Four out of the five studies showed that the oral language intervention had a significant positive impact on at least one area of language. These results together with effect sizes similar to the traditional model of speech and language therapy provide support for the implementation of class-based oral language programmes for children with SLCN. Recommendations on implementing the intervention and further research needs are outlined. Introduction Oral language interventions 1

2 The oral language interventions addressed in this review focuses on the delivery of oral language teaching within a class based setting by school staff. While the traditional model of therapy by Speech and Language Therapists (SLTs) is clinic based and provided by a single speech and language therapist to a single child (Law et al., 2002, p.146), the class based approach follows a consultative model for speech and language therapy provision. In the consultative approach, the SLT acts as consultant to school staff who implements a particular intervention. In the UK, there is a movement from a direct intervention by SLT s to this consultative model (Law et al., 2002). The level of support provided by the SLT varies considerably between interventions, some interventions offering substantial support and professional development for school staff to deliver interventions, while others offer none. The content of oral language intervention programmes differ significantly between programmes. Some programmes focus solely on vocabulary development (Steele & Mills, 2011), while others involve a comprehensive curriculum covering vocabulary, semantics and syntax as well as providing strategies for general support in language development (Wilcox, Gray, Guimond & Lafferty, 2011). Such strategies may include: slowing the rate of speech, interacting at child s eye level, rephrasing questions and comments. Psychological basis The case for class-base approaches to oral language development is rooted in a social constructivist theory of learning (Vygotsky, 1978). The adult provides the dialogue, modelling and recasting of language in its correct form, to the child, who learns through the process of scaffolding. This social constructivist theory of 2

3 language development, purporting that language is a social process is supported by empirical research indicating that a child s level of exposure to language can predict the level of language (Hoff & Naigles, 2002; Huttenlocher et al.,1991; Alston & St. James-Roberts, 2005). While the psychological underpinnings of the class based model do not necessarily differ substantially from the direct therapy, or the traditional model, the former may arguably be a more authentic reflection of the theory, with language instruction being embedded in the natural setting. It is conducive to Vygotsky s (1978) wholelanguage perspective, with the language learner being immersed in language. In addition to the social constructivist view of language learning, the theoretical basis for class based interventions reflects a shift from a within child view of special educational needs (SEN) towards the environmental end of the continuum. While SLTs tend to have a within-child view of language (Dunsmuir, Clifford & Took, 2007) the implementation of class based models for language intervention require a more systemic approach to the delivery of speech and language therapy services. Rationale The rationale for an Educational Psychologist role in class based interventions for oral language development is two-fold. Firstly SLCN is a pervasive need, which is correlated with various academic (Muter, Hulme, Snowling & Stevenson, 2004) and behavioural difficulties (Botting & Conti-Ramsden, 2000; Yew & O Kearney, 2012) and may require a more holistic model of intervention. Secondly, Educational Psychology is rooted in the consultative approach, and is well placed to address the 3

4 systemic, class, group and individual level interventions that are required to adequately address SLCN. Each of these reasons are discussed below. SLCN is the most common childhood SEN. In the UK in 2013, SLCN accounted for 30.6% of the school action plus and statemented cases in primary schools (Department of Education, 2013). There are correlations between SCLN and social and emotional difficulties (Botting & Conti-Ramsden, 2000; Bradshaw &Tipping, 2010), school exclusion (Ripley & Yuill, 2005), literacy (Muter et al., 2004) and wider academic achievement (Aram & Nation, 1980). The pervasiveness and potentially detrimental effects of untreated SCLN calls for a more integrated and systemic approach to the disorder, with Educational Psychologists working together with SLTs to address the issue. This view is supported by the Bercow report (2008) which highlighted unacceptable variation and a lack of equity in the provision of speech and language services for children. The report called for the exploration of the consultative model for speech and language services and recommended collaborative working between education and health services, and the development of more integrated service provision (Bercow, 2008). Review Question Are class-based oral language interventions effective in improving language skills of children with speech language and communication needs. Critical Review of the Evidence Base A literature search was conducted on December 17 th 2013 using the databases PsycInfo, ERIC and Medline. The search was conducted using the terms listed in 4

5 Table 1. Database Search Terms Intervention Setting Participant Group Intervention Efficacy Effectiveness Early years Nursery Pre-school Preschool school kindergarten Pre-kindergarten Language delay SLCN SLI Language Impairment Speech language and Communication need. Each category of terms was searched individually using the abstract field. For example, the first category searched the terms intervention or efficacy or effectiveness. The categories were subsequently combined, from the search history, using the option and. The search resulted in 345 articles from Psychinfo, 305 in ERIC, and 237 in Medline. Some of the studies overlapped between databases. The title and, if necessary abstract of all of these articles were reviewed and those not meeting the inclusion criteria specified in Table 2, were excluded. This resulted in 24 studies which required an inspection of the full article. Of these studies, 19 did not meet the inclusion criteria, resulting in a total of five for inclusion in this review. Figure I provides a flow chart to illustrate this process. A list of the excluded articles and the reason for their exclusion can be found in Appendix 1. 5

6 Figure I. Literature screening process Studies identified from Psych INFO, ERIC and Medline PSYCHINFO Article titles and if necessary, abstract screened using inclusion and exclusion criteria. N=345 ERIC Article titles and if necessary, abstract screened using inclusion and exclusion criteria N=305 Medline Article titles and, if necessary abstract screened using inclusion and exclusion criteria N=237 Full Articles screened using inclusion and exclusion Criteria. N= 24 Studies included in the final review. N=5 6

7 Table 2. Inclusion and exclusion criteria for studies Inclusion criteria 1. Publication type Inclusion Criteria Exclusion criteria Rationale In a peer reviewed journal Not in a peer reviewed journal (i.e. Dissertations) These papers have undergone a level of scrutiny 2. Language Available in the English language Published in a language other than English There is no funding for translations 3. Type of study Collected primary quantitative data Secondary data The use of primary data ensures that any change in language ability is due to the intervention under investigation 4. Design Group Design Single case study The use of group design allows for external variables to be controlled (ie. effects of maturation can be limited) 5. Measures. Uses one or more language assessment tools Does not use a language assessment tool The study addresses the impact on language; a language assessment tool is the only appropriate measure 6. Sample Children aged 2-11 years People not aged 2-11 years The review aims to address children that are in primary and nursery school settings 7. Setting In a mainstream classroom Interventions that are delivered at home, in a special school Allows for some level of homogeneity so that studies can be compared 8. Intervention Oral language programme delivered by staff without a specialism in speech and language therapy 9. Participants Speech delayed, specific language impairment is primary disorder in primary language SLT led programme, SLT assistant led programmes, parent-led, researcherled, Computer based programmes Speech and Language impairment is a secondary disorder. Children with difficulty in acquiring second language The class-based model is the model currently being employed by many schools and nurseries in the UK Allows for some level of homogeneity among participants. Difficulties in acquiring a second language follow a different trajectory 7

8 Table 3. Selected studies for inclusion in review Bickford Smith, A., Wijayatilake, L., & Woods, G. (2005). Evaluating the Effectiveness of an Early Years Language Intervention. Educational Psychology in Practice, 21(3), Gallagher, A. L. & Chiat, S. (2009). Evaluation of speech and language therapy interventions for pre-school children with specific language impairment: a comparison of outcomes following specialist intensive, nursery-based and no intervention. International Journal of Language & Communication Disorders, 44(5), McCartney, E., Boyle, J., Ellis, S., Bannatyne, S., & Turnbull, M. (2011). Indirect language therapy for children with persistent language impairment in mainstream primary schools: outcomes from a cohort intervention. International Journal of Language & Communication Disorders, 46(1), Mecrow, C., Beckwith, J., & Klee, T. (2010). An exploratory trial of the effectiveness of an enhanced consultative approach to delivering speech and language intervention in schools. International Journal of Language & Communication Disorders, 45(3), Wilcox, M. J., Gray, S. I., Guimond, A. B., & Lafferty, A. E. (2011). Efficacy of the TELL language and literacy curriculum for pre-schoolers with developmental speech and / or language impairment. Early Child Research Quarterly, 26, A summary of all of the included studies can be found in Appendix 2. Critical review of Studies The studies were coded for quality using the UCL Educational Psychology Literature Review Coding Protocol, adapted from APA Task Force on Evidence Based Interventions in School Psychology (Kratochwill, 2003). The studies were evaluated using the Gough (2007) Weight of evidence framework which uses three categories with which to assess the studies: Quality of Methodology (Weight of Evidence A), Relevance of Methodology (Weight of Evidence B) and Relevance of Evidence to the 8

9 Review Question (Weight of Evidence C). The average score in each of these three categories is taken to provide an Overall Weight of Evidence (Weight of Evidence D). Appendix 3 contains information on the criteria for the weight of evidence in each category in addition to information on how WOE A was calculated for each study. The weight of evidence of each of the studies in this review is found in Table 4. Table 4. Overall weight of evidence Reviewed Study Bickford- Smith et al. (2005) Gallagher and Chiat (2009) McCartney et al.(2011) Mecrow et al. (2010) Wilcox et al. (2011) WoE A Methodological Quality WoE B Methodological Relevance WoE C Relevance to the Review Question WoE D Low Low Low Low Low Medium Medium Medium Low Medium Low Low Low Low Medium Low Medium Medium High Medium Participants One of the studies (Wilcox et al., 2011) was conducted in Arizona, in the United States, one in Scotland (McCartney, Boyle, Ellis, Bannatyne & Turnbull, 2011), two in London (Gallagher & Chiat, 2009, and Bickford-Smith Wijayatilake, & Woods, 2005), and one in Newcastle, UK (Mecrow, Beckwith, & Klee, 2010). The specific nature of the SLCN varied considerably between the studies as did the method of selecting participants. Three of the studies identified participants as those 9

10 who already had an SLCN diagnosis: Mecrow et al. (2010) selected children who were on School Action Plus, for an SLCN prior to the study. Gallagher and Chiat (2009) selected children who were on the waiting list for Speech and Language services, and Wilcox et al. (2011) selected children who had a Delayed Speech and Language Impairment (DSLI) as identified by the school district. One study (Bickford- Smith et al., 2005) identified the school (which was the result of a Head Teacher request for Educational Psychology services) and subsequently tested all children in the nursery, classifying those with delayed language as those who scored one standard deviation below the mean. While the Gallaher and Chiat (2009) and Mecrow et al., (2010) studies used the need for SLT involvement as their criteria, the McCartney et al. (2011) study included those with an SLI diagnosis and scored 1.5 standard deviations below the mean yet did not require the specialist skills and knowledge of an SLT. Three studies (Bickford-Smith et al., 2005; Gallagher and Chiat, 2009; Wilcox et al., 2011) identified preschool age participants (3-5 years) whereas the remaining two (McCartney et al., 2011; Mecrow et al., 2010) used children aged 4 to 6. All studies reported SLCN as the only SEN of participants. In addition, three of the studies (McCartney et al., 2011; Wilcox et al., 2011; Bickford-Smith et al., 2005) specifically screened for non-verbal skills, and excluded children below a floor level in this area, thereby ensuring the verbal domain as the sole area of need. Gallagher and Chiat (2009) did not use nonverbal test scores to exclude participants; however, it was clear that none of the children had an ASD diagnosis, no EBD, neural damage or hearing damage. Mecrow et al. (2010) did not provide information on the nonverbal abilities of their participants. 10

11 Design All five papers used a quantitative approach, and each took pre and post measures of the groups before and after the intervention. With the exception of Mecrow et al. (2010) all studies used a between participants design, with Mecrow et al. (2010) using pre and post measures within one group of participants (with each participant acting as their own control). Of the four studies using between participants design, two studies used a no intervention group (Bickford-Smith et al., 2005 and Wilcox et al., 2011) which contributed to their low to medium ratings in WOE B. One study (McCartney et al., 2011) used the traditional Speech & Language therapy model as the control. And one study (Gallagher & Chiat, 2009), applied a two level approach, using one control group, as well as a nursery based intervention and a speech and language therapy group which contributed to a higher rating on WOE B. None of the studies counterbalanced the change agents; this was due to the fact that they were class based interventions. The Gallagher and Chiat (2009) study was the only one that randomly assigned participants to a control and intervention groups. The Wilcox et al. (2011) study randomly assigned classes of children to control or intervention conditions, which resulted in a lower weight of evidence as effects may have been compounded by other factors within the conditions. McCartney et al. (2011) used a historical cohort control, and Bickford-Smith et al. (2005) used the morning session of the nursery as the intervention, and the afternoon session as the control. A power analysis was conducted to determine if the studies had sufficient number of participants to detect a significant effect. This criteria is included in WOE A. To determine if the study had sufficient participants, the researcher first reviewed 11

12 previous meta-analyses of language interventions to determine the expected effect size of such an intervention. As there were no prior meta analyses on class based interventions for oral language, various other studies were reviewed. The metaanalyses by Law, Garrett and Nye (2004) provided average effect sizes across language outcomes (phonology, vocabulary, syntax) as d= This was for interventions provided by speech and language therapists. Roberts and Kaiser (2010) conducted a meta-analyses of parent led interventions for children with SLCN and found an average effect size of d= 0.52 across the outcomes (expressive language, receptive language, vocabulary). Finally, while no meta-analyses have yet been conducted on class based interventions, a study by Fricke, Bower-Crane, Hayley, Hulme and Snowling (2013) reported effect sizes of d= 0.49 across the outcome measures (CELF scores, grammar, comprehension, narrative). Based on this research, it was concluded that one would expect a small to medium effect for oral language based interventions. Intervention The intervention quality was assessed using the following factors: time allocated to the intervention, the degree to which the approach is manualised, breadth of content, and treatment fidelity. These are some of the factors have been outlined by Law et al. (2010) as important to consider in evaluating language interventions. The quality of the intervention is reflected in WOE C. Time: The least intensive programmes with regard to time allocation were Gallagher and Chiat (2009) which implemented the programme once per week, and McCartney et al. (2011) which implemented the programme one-two times per week. This contributed to low to medium ratings on WOE C for these studies respectively. The 12

13 remaining studies implemented the programme four to five times per week varying from 20 minutes Bickford -Smith (2005) to full day sessions (Wilcox et al., 2011). It is acknowledged that in the Wilcox et al. (2011) intervention, parts of the full day session were dedicated to literacy skills, and it was not solely an oral language intervention. Programme Manual: Two of these studies had a manual for the intervention: Wilcox et al. (2011) provide a comprehensive curriculum package which was complete with books, props, lesson plans and professional development plans. McCartney et al.(2011) also contained a less prescriptive manual with activities. While it was not manualised the intervention in the Gallagher and Chiat (2009) study provided detailed plans of the lessons, and highlighted the difference between the class based intervention and the intensive (speech and language therapist led) groups. Breadth of Content: Four of the interventions reviewed had a relatively wide breadth of content which focused on more than two elements of language, this was reflected in the medium to high ratings in WOE C in all four studies. McCartney et al. (2011): supported comprehension monitoring, and the development of vocabulary, grammar and narrative. Gallagher and Chiat (2009) included: modelling, sentence recasting, imitation. Wilcox et al. (2011) targeted vocabulary and complex language (sentence length and complexity). Bickford-Smith et al. (2005) had the least breadth of content with a focus only on vocabulary acquisition. The intervention aimed to teach ten words per week. This was reflected in the low rating in WOE C. Fidelity: Wilcox et al. (2011) and Gallagher and Chiat (2009) were the only studies to report fidelity in implementing the programme which contributed to their medium to high ratings in WOE C. The remaining three did not report the level to which the 13

14 programme was implemented thereby lowering the rating in WOE C for these studies. Outcome Measures Outcome measures differed for each study, although the CELF was the most common measurement, with four of the studies using a version of this (CELFP2 UK, CELF 3 UK ). None of the studies reported the validity of the CELF as a language measure. The CELF is however a well-known and widely used assessment tool and has been standardised for the UK population. Outcomes were categorised according to the area of language that was being measured: receptive vocabulary, receptive grammar, receptive language (overall), expressive vocabulary, expressive grammar, expressive, narrative, expressive (overall). Effect sizes for each study were calculated using the formula provided by Becker (1988), measuring within person change. This method was selected in order that effect sizes were consistent across studies. While some studies provided effect sizes, all effect sizes were recalculated by the researcher to ensure accurate comparisons. Table 5 shows the outcomes for each study and indicates the effect size for each outcome measure. Effect size ratings of small, medium or large was based on Cohen s criteria (Cohen, 1988). 14

15 Table 5. Effect sizes for each language outcome measure Authors Outcome measures Effect size Significantly Bickford Smith et al. (2005) Receptive Language Vocabulary Grammar Expressive Language Vocabulary Small Large Medium higher than no intervention? No Yes No Significantly lower than SLT N/A Weight of Evidence Low Gallagher and Chiat (2009) McCartney et al. (2011) Mecrow et al. (2010) Receptive Language Vocabulary Grammar Expressive Language Vocabulary Grammar Expressive Language Overall Language Overall (parent questionnaire) Receptive Language Overall Expressive Language Overall Total Language Overall: Receptive Language Vocabulary Grammar Expressive Language Vocabulary Grammar Narrative None Large Large Large Small None Medium Small Small Small Small/med** Small* Medium* Small No Yes No No No Not reported N/A Yes Yes Yes No Yes No Not reported No No Not reported Medium Low N/A N/A Low Wilcox et al. (2011) Receptive Language Receptive Language Overall Receptive Vocab (Spring measure) Expressive Language Narrative Expressive Vocab (Spring measure) Overall expressive language Medium Medium Small-Large. Large Small No Yes Yes Yes Yes N/A Medium *p<0.05: within group change **p<0.01 within group change 15

16 Primary Outcome Vocabulary Four studies included vocabulary as one of the outcome measures; all showed small to large effect sizes. Effect sizes reported for vocabulary for the two meta-analyses were within the small to medium range (Law et al., 2004; Roberts & Kaiser, 2010). One explanation for the large variations in effect sizes for the vocabulary outcome measure may be attributed to the different methods of measurement. Wilcox et al. (2011) used the VOCAB measure, which was developed specifically for that investigation. While Wilcox et al. (2011) did report a moderate correlation for this measure with standardised tests (the CELF), the correlation is for overall language score, not specifically vocabulary. In the Gallagher and Chiat (2009) study, the outcome measure for vocabulary was the Renfrew Action Picture test (expressive) and the BPVS (receptive), the reliability and validity of which was not reported in the paper. The studies reporting small to medium effect sizes all used the CELF. While all studies reported small to medium effect sizes for vocabulary, only two reported effects to a statistically significant level. Wilcox et al. (2011) reported a significant difference between groups in the area of vocabulary (p<0.0001), and Mecrow et al. (2010) reported significant differences between groups for expressive vocabulary. The nature of the vocabulary intervention differed between studies with some providing explicit vocabulary teaching in addition to embedding new words in the context of stories (Wilcox et al., 2011), while others did not provide direct instruction in vocabulary (Gallagher & Chiat, 2009). The intervention described in the Bickford- 16

17 Smith et al. (2005) study also appeared to address the semantic elements of vocabulary, however little information is provided on the intervention, as reflected in the low weighting in WOE C. In their meta-analysis on learning vocabulary, Stahl and Fairbanks (1986) found that for vocabulary learning to be successful, the intervention must include: definitional and contextual information. in-depth meaning and multiple repetitions or exposures to new words. Of the reviewed studies, only the intervention in the Wilcox et al. (2011) involved the teaching of vocabulary this thoroughly. Only the studies that achieved a Medium for overall weight of evidence were also able to achieve large effect sizes; Gallagher and Chiat (2009) for expressive vocabulary and Wilcox et al. (2011), also for expressive vocabulary. The common features that these studies shared in achieving the medium weight of evidence was the intensity of the language intervention, both of which featured heavily in vocabulary. Interestingly however this explanation does not hold for receptive vocabulary; the intensity of the intervention may have resulted in children feeling more confident in their expressive language which may have led to higher scores. Grammar Grammar showed a medium to large effect across studies, and was the only outcome measure to provided significant results across studies, both between (Bickford-Smith et al., 2005; Gallagher & Chiat, 2009), and within group participants, (Mecrow et al., 2010). The effect sizes and significant results are not related to the quality of the study; two of the three were deemed to be of low quality. No trends could be established between the quality of the study and the outcomes with regard to grammar, as only one of the two medium rated studies included a measure of 17

18 grammar. As two of the studies that reported the significant results (Bickford-Smith et al., 2005 and Mecrow et al., 2010) were of low quality the results should be interpreted with caution. With regard to the nature of the interventions, neither the Gallagher and Chiat (2009) nor the Bickford-Smith et al. (2005) study, include any explicit grammar teaching as part of the intervention. Grammar may have been indirectly addressed in story retelling part of the intervention (Gallaher & Chiat, 2009), and the linguistic concepts activities. This may suggest that children with SLCN are able to learn correct grammatical structures without explicit teaching, if they are provided with sufficient modelled language. Narrative Only two studies included expressive narrative language as an outcome measure (Mecrow et al., 2010 and Wilcox et al., 2011), one of which found significant differences between participants (Wilcox et al., 2011) and the other no significant changes were reported (Mecrow et al., 2010). The effect sizes ranged from small (Mecrow et al., 2010 and Wilcox et al., 2011) to large (Wilcox et al., 2011). The Wilcox et al. (2011) study use three different measures for this outcome thereby presenting a strong case for the effectiveness of the intervention on narrative skills. The intervention in the Wilcox et al. (2011) study promoted strategies targeting the acquisition of complex language skills which may have contributed to this significantly large effect in this area. As only two of the studies included a measure of narrative skills, no trend could be established with regard to the low vs, medium weight of evidence ratings. However, 18

19 the Wilcox et al. (2011) study which achieved the medium rating did produce both a significant effect, between groups, and was able to achieve large effect sizes on some measures. This was not the case for the Mecrow et al. (2010) study which received a low weighting for overall weight of evidence: it did not produce a significant result and achieved only a small effect size. Receptive Language A measure of receptive language, as a composite score, was reported in two of the studies (McCartney et al., 2011 and Wilcox et al., 2011), and both reported no significant difference between or within groups and small to medium effect sizes. The CELF was used in both cases. The control group used in McCartney et al. (2011) study was a speech and language therapy control group. The large effect size and no significant difference between groups might suggest that class based intervention was as effective as the traditional speech and language model. However, as the within group change for the classbased intervention was also reported as insignificant then an alternate interpretation might be suggested: that neither class based nor speech and language therapy interventions are effective. The study however, was underpowered as reflected in the WOE A. Expressive Language A measure of expressive language was reported in three of the studies (Gallagher & Chiat, 2009, McCartney et al., 2011, & Wilcox et al., 2011), none of which reported significant results, and reported small to medium effect sizes. While the Law et al. (2004) meta-analysis did not provide an effect size for the expressive language 19

20 category, it is consistent with their measure of the effect of intervention on overall language score, which was small. Roberts and Kaiser s meta-analysis on parental interventions for SLCN reported a medium effect for expressive language. Conclusion This review evaluated five studies that provided class-based interventions for children with SLCN. Three studies were rated low on the overall quality of evidence, while two achieved a medium overall weight of evidence. The weight of evidence however did not have an overall bearing on the findings, with both the low and medium rated studies achieving a range of no effect to large effect sizes on the various language skill categories. The low to medium weight of evidence for these studies reflects the difficulty in conducting research with special populations in mainstream schools. There are a number of factors that make comparisons between studies difficult including different measurement tools, heterogeneous population of SLCN, varying intensity levels of the intervention (time, breadth of content), and the lack of reporting of the fidelity of implementation. While there are promising results with regard to the effect the interventions for children with SLCN, the lack of controlled variables in the studies make it difficult to determine the most important element of the intervention in producing the effect. Similar methodological difficulties for language interventions have been outlined in the review by Parkinson and Humphrey (2008). Despite the methodological weaknesses, this review finds promising support for class-based interventions for children with SLCN. With effect sizes consistent with more traditional models of speech and language intervention (Law et al., 2004), and the previously established need for a more consultative approach to speech and 20

21 language therapy (Bercow, 2008), then class based interventions offer a viable intervention for children with SLCN. In recommending this approach to speech and language provision, a number of factors need to be considered. These factors are included in the form of recommendations below. Recommendations In order to further understand the critical components of an intervention, and for whom it works, there are a number of recommendations to be made for future research: Information about interventions: Information regarding the precise nature of the intervention is needed to ensure that comparisons can be made across studies, effective elements of the intervention can be identified, and replication is possible. Measures: In order to compare data across studies, a degree of consistency in measurement is necessary. Measurement scores also need to be disaggregated into component parts in order to ensure comparisons are possible. Follow up: Follow up measures need to be taken after the intervention to assess if progress during the intervention is sustained. None of the studies in the current review reported any follow up measures. Participants: due to the broad scope of SLCN, it is imperative that researchers provide information about the nature of the SLCN in order to allow for relevant comparisons, and determine whether some interventions are more relevant for a particular need. Role of school staff in supporting speech and language: Further research is needed on the most effective ways in which school staff can support speech 21

22 and language interventions. Law et al., (2002) reported that the consultative model can only work if there is someone there to consult; further research is needed to assess effective systems for this. In conclusion, this review provides promising support for class based language interventions and it is recommended that schools, speech and language therapists and Educational Psychologists collaborate to implement class-based language instruction for children with SLCN. References Alston, E. & St. James-Roberts, I. (2005). Home environments of 10-month-old infants selected by the WILSTAAR screen for pre-language difficulties. International Journal of Language & Communication Disorders, 40, Aram, D. M. & Nation, J. E. (1980). Preschool language disorders and subsequent language and academic difficulties. Journal of Communication Disorders, 13, Baxendale, J. & Hesketh, A. (2003). Comparison of the effectiveness of the Hanen Parent Programme and traditional clinic therapy. International Journal of Language and Communication Disorders Oct-Dec Vol.38, No. 4, Becker, B. J. (1988). Synthesizing standardized mean-change measures. British Journal of Mathematical and Statistical Psychology,41, Bickford Smith, A., Wijayatilake, L., & Woods, G. (2005). Evaluating the Effectiveness of an Early Years Language Intervention. Educational Psychology in Practice, 21(3), Bercow, J. (2008). The Bercow Report: A review of services for children and young people (0 19) with speech language and communication needs. Nottingham: Department for Children, Schools and Families. 22

23 Botting, N. & Conti-Ramsden, G (2000). Social and behavioural difficulties in children with language impairment. Child Language Teaching and Therapy 16, Cohen, J. (1988). Statistical power analysis for the behavioural sciences. New Jersey: Lawrence Erlbaum Associates, Inc. Publishers. pp Department of Education, /SFR _Text.pdf Durkin, K.& Conti-Ramsden, G. (2010). Young people with specific language impairment: A review of social and emotional functioning in adolescence. Child Language Teaching and Therapy, 26, Fricke, S., Bowyer-Crane, C., Haley, A. J., Hulme, C., & Snowling, M. J. (2013). Efficacy of language intervention in the early years. Journal of Child Psychology and Psychiatry, and Allied Disciplines, 54(3), Gallagher, A. L. & Chiat, S. (2009). Evaluation of speech and language therapy interventions for pre-school children with specific language impairment: a comparison of outcomes following specialist intensive, nursery-based and no intervention. International Journal of Language & Communication Disorders / Royal College of Speech & Language Therapists, 44(5), Gough, D. (2007). Weight of Evidence: a framework for the appraisal of the quality and relevance of evidence. Research Papers in Education, 22(2), Hoff, E. & Naigles, L. (2002). How children use input to acquire a lexicon. Child Development, 73, Huttenlocher, J., Haight, W., Bryk, A., Seltzer, M., & Lyons, T. (1991). Early vocabulary growth: Relation to language input and gender. Developmental Psychology, 27, Kratochwill, T. R. (2003). Task force on evidence-based practice interventions in school psychology. Retrieved on January 25 th 2014 from: SSP%20EBI%20Manual.pdf Law, J., Garrett, Z., & Nye, C. (2004). The efficacy of treatment for children with developmental speech and language delay/disorder: a meta-analysis. Journal of Speech, Language, and Hearing Research : JSLHR, 47(4), Law, J., Lee, W., Roulstone, S., Wren, Y., Zeng, B., & Lindsay, G. (n.d.). What Works ': Interventions for children and young people with speech, language and communication needs. 23

24 Law, J., Lindsay, G., Peacey, N., Gascoigne, M., Soloff, N., Radford, J., & Band, S. (2002). Consultation as a model for providing speech and language therapy in schools: a panacea or one step too far? Child Language Teaching and Therapy, 18(2), McCartney, E., Boyle, J., Ellis, S., Bannatyne, S., & Turnbull, M. (2011). Indirect language therapy for children with persistent language impairment in mainstream primary schools: outcomes from a cohort intervention. International Journal of Language & Communication Disorders / Royal College of Speech & Language Therapists, 46(1), Mecrow, C., Beckwith, J., & Klee, T. (2010). An exploratory trial of the effectiveness of an enhanced consultative approach to delivering speech and language intervention in schools. International Journal of Language & Communication Disorders / Royal College of Speech & Language Therapists, 45(3), Muter, V., Hulme, C., Snowling, M.J., & Stevenson, J. (2004). Phonemes, rimes, vocabulary and grammatical skills as foundations of early reading development: Evidence from a longitudinal study. Developmental Psychology, 40, Parkinson, G., & Humphrey, N. (2008). Intervention for children with language impairments: a model of evidence-based outcome research. Journal of Research in Special Educational Needs, 8(1), Ripley, K., & Yuill, N. (2005). Patterns of language impairment and behaviour in boys excluded from school. The British Journal of Educational Psychology, 75(Pt 1), Roberts, M. & Kaiser, A. P. (2011). The Effectiveness of Parent-Implemented Language Interventions: A Meta-Analysis. American Journal of Speech-Language Pathology, 20(August), Steele, S. C. & Mills, M. T. (2011). Vocabulary intervention for school-age children with language impairment: A review of evidence and good practice. Child Language Teaching and Therapy, 27(3), Stahl, S.. & Fairbanks, M.M. (1986). The effects of vocabulary instruction: A modelbased meta-analysis. Review of Educational Research 56: Vygotsky, L. (1978) Mind in society. Cambridge, MA: Harvard University Press. Wilcox, M. J., Gray, S. I., Guimond, A. B., & Lafferty, A. E. (2011). Efficacy of the TELL language and literacy curriculum for pre-schoolers with developmental speech and / or language impairment. Early Child Research Quarterly, 26, Yew, S. G. K. & O Kearney, R. (2013). Emotional and behavioural outcomes later in childhood and adolescence for children with specific language impairments: metaanalyses of controlled prospective studies. Journal of Child Psychology and Psychiatry, and Allied Disciplines, 54(5),

25 Appendix 1: Excluded Studies Excluded Studies 1 Boyle, J., McCartney, E., O Hare, A., & Forbes, J. (2009). Direct versus indirect and individual versus group modes of language therapy for children with primary language impairment: principal outcomes from a randomized controlled trial and economic evaluation. International Journal of Language & Communication Disorders, 44(6), Davies, P., Shanks, B., & Davies, K. (2004). Improving narrative skills in young children with delayed language development. Educational Review, 56(3), Dickson, K., Marshall, M., Boyle, J., McCartney, E., O Hare, A., & Forbes, J. (2009). Cost analysis of direct versus indirect and individual versus group modes of manual-based speech-andlanguage therapy for primary school-age children with primary language impairment. International journal of language & communication disorders / Royal College of Speech & Language Therapists, 44(3), Reason For Exclusion Criteria 8: The intervention was delivered by SLT assistants Criteria 9: Participants. Children did not have SLCN. Criteria 8: The intervention was delivered by SLT assistants 4 Ebbels, S. (2007). Teaching grammar to school-aged children with specific language impairment using Shape Coding. Child Language Teaching and Therapy, 23(1), Criteria 8: The intervention was delivered by the researcher 5 Lafferty, A. E., Gray, S., & Wilcox, M. J. (2005). Teaching alphabetic knowledge to pre-school children with developmental language delay and with typical language development. Child Language Teaching and Therapy, 21(3), Loeb, D. F., Gillam, R. B., Hoffman, L., Brandel, J., & Marquis, J. (2009). The effects of Fast ForWord Language on the phonemic awareness and reading skills of school-age children with language impairments and poor reading skills. American journal of speech-language pathology / American Speech- Language-Hearing Association, 18(4), Motsch, H.-J., & Riehemann, S. (2008). Effects of Context- Optimization on the acquisition of grammatical 25 case in children with specific language impairment: an experimental evaluation in the classroom. International Journal of Language & Communication Disorders / Royal College of Speech & Criteria 5: Measures. The study did not include language measures Criteria 5: Measures. The study did not include language measures Criteria 7 Setting: Intervention was delivered in a special school,

26 Language Therapists, 43(6), Munro, N., Lee, K., & Baker, E. (2008). Building vocabulary knowledge and phonological awareness skills in children with specific language impairment through hybrid language intervention : a feasibility study. 9 Ritter, M. J., & Saxon, T. F. (2010). Classroom-Based Phonological Sensitivity Intervention (PSI) Using a Narrative Platform: An Experimental Study of First Graders At Risk for a 10.Reading Disability. Communication Disorders Quarterly, (1), Sajaniemi, N., Suhonen, E., & Kontu, E. (2010). Verbal and non verbal development in SLI children after early intervention. Early Child Development and Care, 180(4), Smith-Lock, K. M., Leitao, S., Lambert, L., & Nickels, L. (2013). Effective intervention for expressive grammar in children with specific language impairment. International Journal of Language & Communication Disorders / Royal College of Speech & Language Therapists, 48(3), Smith-Lock, K., Leitão, S., Lambert, L., Prior, P., Dunn, A., Cronje, J., & Nickels, L. (2013). Daily or weekly? The role of treatment frequency in the effectiveness of grammar treatment for children with specific language impairment. International Journal of Speech-Language Pathology, 15(3), Tyler, A. a, Lewis, K. E., Haskill, A., & Tolbert, L. C. (2003). Outcomes of different speech and language goal attack strategies. Journal of speech, language, and hearing research : JSLHR, 46(5), Retrieved from Criteria 8: The intervention was delivered by SLT assistants Criteria 5: Measures. The study did not include language measures (only reading measures). Criteria 8: Not explicit who the change agent was. Criteria 7: Setting. Special School Criteria 7: Setting. Special school setting Criteria 8: The interventions were delivered by graduate interns. 14 Tyler, A. a., Gillon, G., Macrae, T., & Johnson, R. L. (2011). Direct and Indirect Effects of Stimulating Phoneme Awareness vs. Other Linguistic Skills in Pre-schoolers With Co-occurring Speech and Language Impairments. Topics in Language Disorders, 31(2), Criteria 8: The interventions were delivered by Senior or Master s level speechlanguage pathology students who were trained on the interventions 26

27 15 Van Kleeck, A., Vander Woude, J., & Hammett, L. (2006). Fostering literal and inferential language skills in Head Start pre-schoolers with language impairment using scripted booksharing discussions. American Journal of Speech-Language Pathology / American Speech-Language-Hearing Association, 15(1), Washington, K. N. (2013). The Association Between Expressive Grammar Intervention and Social and Emergent Literacy Outcomes for Pre-schoolers With SLI. American Journal of Speech Language Pathology, Yoder, P., Camarata, S., & Gardner, E. (2005). Treatment Effects on Speech Intelligibility and Length of Utterance in Children with Specific Language and Intelligibility Impairments. Journal of Early Intervention, 28(1), Criteria 8: Intervention delivered by graduate and undergraduate research assistants Criteria 8 : Intervention by Speech and language pathologist. Criteria 8: Intervention delivered by a psychology undergrad 19 Ziolkowski, R. a., & Goldstein, H. (2008). Effects of an Embedded Phonological Awareness Intervention During Repeated Book Reading on Preschool Children With Language Delays. Journal of Early Intervention, 31(1), Criteria 5: Measures. Language measures were not used, only reading. 27

28 Appendix 2: Summary of Studies Bickford-Smith et al. (2005) Participants Intervention Design Measures Outcomes 2 part intervention: Non randomized design: 1) Directly taught language The morning group at the programme nursery was designated 2) The creation of a language rich nursery environment. Number: 6 children with delayed language. Age: 3 years five months to 4 years 4 months. Nursery school in outer London The directly taught language programme focused on teaching vocabulary (10 words per week), teaching was reinforced with Makaton signs, rebus symbols, real objects and photographs. The group was taught by a member of the nursery staff. The staff member delivering the program was provided with weekly support from a speech and language therapist. The creation of the language rich environment involved: visually and verbally reinforcing target words, expanding children s language when repeating back, model language to children. Ran for 10 weeks as the intervention group. The afternoon group was the control group. (** It is unclear from the paper how many children were in each group). CELF P subtests: Basic Concepts (assesses a child s understanding of modifiers relating to attributes, Dimension, quantity and position). Sentence Structure (assesses a child s understanding of early acquired sentence formation rules). Formulating Labels (assesses a child s ability to name pictures that represent nouns And verbs). Test on receptive and expressive knowledge of the first 100 words (vocabulary test). Parental questionnaire to assess which of the first 100 words their child knew The intervention group showed significantly more progress than the control group on only one of the measures: sentence structure, which assesses receptive language. The intervention group showed progress in the other areas (basic concepts and formulating labels), but not to a significant level. 28

29 Gallagher and Chiat (2009) Participants Intervention Design Measures Outcomes Children received group instruction in Reynell developmental the nursery setting. The instruction scales III comprehension was conducted by nursery staff with subtest : measures: the support of a speech and Receptive language therapist. grammar. Expressive The intervention focused on the grammar following areas of language: Understanding and use of linguistic British Picture Vocabulary concepts such as colour, size, spatial Scale: measures: prepositions. 24 children aged 3 years 6 months to 5 years, recruited from specialist speech and language therapy waiting list in Lambeth, London. Understanding and use of grammatical markers e.g. past -ed endings, plural -s. Understanding and use of utterances including increasing numbers of key information words. Understanding and use of a list of topic-based vocabulary. Attention to adult-led tasks for an increasing length of time. Time: one hour per week in small groups. Speech and language therapist involved in 12 hours of training. Instruction implemented by nursery staff in between. Randomized design: Children were randomly assigned to one of three intervention groups: 1) Traditional speech and language therapy delivered by Speech and language therapist 2) Consultative design: class based intervention 3) Control group: no intervention Blind assessment receptive vocabulary Renfrew word finding test: Expressive vocabulary Renfrew Action Picture test: measures: expressive language. Parent/carer questionnaire. Measures; Parental perception of child s language. Nursery Based Group made more progress than no intervention group on one measure (comprehension of grammar), but showed no significant differences on any of the other measures. Intensive group showed significantly more progress than the nursery based group on all measures with the exception of expressive grammar, where there were no significant differences. Intensive treatment group showed large effects on all measures (ranging from d=1.26 to