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Doctorate in Educational and Child Psychology Caroline Monteith

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Case Study 1: An Evidence-Based Practice Review Report

Theme: School Based Interventions for Learning

How effective are language interventions in improving language and literacy skills in

preschool and primary age children from low-income families?

Summary

This systematic literature review evaluates the impact of school-based, oral language

interventions on the language and literacy skills of children from low-income families. These

oral language interventions targeted teacher-student interactions and often built capacity in

schools through professional development of school staff. This model is increasingly

employed in the UK whereby external agencies, such as Speech and Language Therapists

(SALT), work collaboratively with schools to provide support to children with weak language

skills. This review critically evaluates five studies that investigated the effectiveness of

school-based, oral language interventions with socio-economically disadvantaged children.

The studies assessed the impact of the oral language intervention on measures including

receptive language, expressive language, vocabulary, grammar, narrative skills and reading

attainment. All studies found the oral language intervention had a significant positive impact

on at least one area of language of children from low-income families, providing support for

their use in schools. Recommendations on implementing the intervention and further

research needs are outlined.

Introduction

Oral language interventions

In the UK, there has been movement away from traditional models of clinic-based,

single-child interventions by Speech and Language Therapists (SALTs) towards a systemic,

class-based approach adopting a consultative model (Law et al., 2002). The consultative


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approach has been found to be successful (Mecrow, Beckwith, & Klee, 2010) and involves

SALT acting as consultants to school staff who implement the intervention (Hartas, 2004).

The level of support provided by the SALT varies considerably from very little to substantial

professional development for school staff.

An unpublished meta-analysis examined the effect of preschool curriculum

interventions on vocabulary development in socio-economically disadvantaged children

(Darrow, 2009), however this current review will develop their findings further by focusing

specifically on language interventions, and will explore the wider impact on language and

literacy skills. Some studies in this review did use vocabulary as an outcome measure,

although this was not solitary.

This review focuses on school-based language interventions, which target teacher-

student interactions, as opposed to student-student interactions, following evidence of

significant gain on pre-schoolers’ oral language competence being associated with

increased time talking with adults, rather than children (McCartney, 1984).

Competency in using spoken language involves a number of skills such as

vocabulary knowledge, awareness of grammar and syntax, and knowledge of narrative

structure, and are all fundamental to the development of successful reading comprehension

(Carroll, Bowyer-Crane, Duff, Hulme, & Snowling, 2011). There is wide variation between the

content of oral language interventions however often elements of interactive discourse or

dialogic reading are included, which is the most widely validated means of enhancing

children’s oral language skills (Whitehurst & Lonigan, 2001).

Psychological basis

The social constructivist theory of learning (Vygotsky, 1978) purports that the

development of children’s oral language is a social process through collaborative

interactions with others (Bohannon & Bonvillian, 2001). Research (e.g. Hoff & Naigles, 2002)

has demonstrated that a child’s exposure to language is associated with their level of


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language and thus supports this theory. This theory underpins the case for class-based

approaches to oral language development and requires school staff to provide a rich

dialogue, modelling and repeating the child’s language in its correct and expanded form, so

the child learns through scaffolding. Although such social interactions occur through

traditional clinic-based interventions, the move towards language instruction being

embedded in the classroom, allows the child to be immersed in language in their natural

setting. It reflects a shift from a within-child view of language (Dunsmuir, Clifford, & Took,

2006) towards a more eco-systemic approach, which considers the impact of environmental

influences (Bronfenbrenner, 1979).

Rationale

Several studies show that a large proportion of children from low-income families

enter preschool with poorer language skills compared to their middle-class peers (e.g.,

Whitehurst et al., 1999). Although there is variability across families (Payne, Whitehurst, &

Angell, 1994), many children from low-income families have inadequate access to books and

other literacy opportunities (Neuman & Celano, 2001) and reduced communicative

exchanges. Hart and Risley (1995) reported low-income children had two to three times less

opportunities to converse with their parents compared to middle-class children. Research

suggests the gap in attainment between their peers persists as children progress from

elementary to high school (Puma et al., 1997). Moreover, evidence indicates that oral

language difficulties in the early years compromises psychosocial development and can

predispose children to long-term mental health problems (Schoon, Parsons, Rush, & Law,

2010) as well as being linked with externalised behaviour disorders, which can further impact

these children’s access to education (Snow & Powell, 2011).

Earlier research suggested nursery staff felt under pressure to move children towards

reading and writing often before they had the necessary foundations in terms of their speech

and language skills (Bickford-Smith, Wijayatilake, & Woods, 2005). Current preschool and

primary school curricular, however, identifies ‘communication and language’ to be one of the


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three prime areas in the statutory framework for the early years foundation stage

(Department for Education, 2014) and ‘language and literacy’ is identified as a key area in

the primary curriculum (Department for Education, 2014) with spoken language specifically

mentioned. Previous findings suggested the average lead teacher engaged in extended talk

with children on one topic only 14% of the time during free play (Dickinson, McCabe, &

Clark-Chiarelli, 2004). Moreover, despite the well-known benefits of book reading, teachers

read on average less than 8 minutes per day, with only 4% of teachers reading more than 20

minutes per day (NICHD Early Child Care Research Network, 2000). This lack of dialogue

between teachers and students results in limited opportunities for children to talk and receive

feedback and hampers language development. Considerable evidence indicates that many

aspects of oral language play a critical role in laying the foundation for literacy skills (Storch

& Whitehurst, 2002). In addition, teachers feel extremely underprepared to teach beginning

readers (Harper & Rennie, 2009). Literacy interventions have been found to change

teachers practices (Dickinson et al., 2004). These findings highlight the need for

interventions to not only address the oral language skills of children but also build capacity

through professional development to enhance the use of talk, and raise awareness of its

importance in schools.

Review Question:

“How effective are language interventions in improving language and literacy skills in

preschool and primary age children from low-income families?”

Critical Review of the Evidence Base

On 19 January 2016 a literature search was conducted using the electronic

databases PsycINFO, Web of Science and ERIC. Table 1 outlines the search terms used.

Each category was searched individually and the results were subsequently combined using

the option ‘AND’ in the search history.


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Table 1.

Search Terms

Intervention (TITLE) Participants(ABSTRACT)

Participants (TITLE) Outcomes(TITLE)

talk OR language ORverbal ORcommunication ORoral OR interpersonalOR discourse ORdiscuss* ORcollabora*

*denotes wildcard

Children ORprimary-age ORelementary ORpre-school ORkindergarten ORreception ORinfants OR juniors

Deprived ORPoor ORLow-income ORLow socioeconomic status ORUnderprivileged ORDisadvantaged ORAt-risk OR free school meals

literacy ORwriting ORreading

The search yielded 145 studies, 60 of which were duplicates. The title and abstract of

the remaining articles were reviewed and those not meeting the inclusion criteria specified in

Table 2, were excluded. An ancestral search was then conducted on the remaining papers,

screening for titles that contained relevant terminology. These records were added to the 9

remaining studies from the electronic database search making 24 studies to be screened at

full text level. Any papers that did not meet the inclusion criteria specified in Table 2 were

excluded. After removal of unsuitable studies, five papers remained and these were included

in the review. The flow diagram depicted in Figure 1 summarises this process. Table 3

includes the full list of included studies, and Appendix A contains the list of excluded studies.


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Table 2.

Inclusion/Exclusion Criteria

Criterion Inclusion criteria Exclusion criteria Rationale1) Participants

/ Settinga) Children must beaged between 0 and11 years of age

b) Children must befrom a low-incomefamily

c) Intervention musthave taken place inschool

d) Children must nothave a specificlanguage impairmentor learning difficulty

a) Children are notaged between 0 and11 years of age

b) Children are notfrom a low-incomefamily

c) Intervention hasnot taken place inschool

d) Children who havespecific languageimpairments or otherknown learningdifficulty

This review is concerned withschool-based interventions inpreschools and primaryschools for children from low-income families with no otherknown cause of specificlanguage delay.

2) Type ofPublication

a) Must be publishedin a peer reviewedjournal

b) Must be publishedon or after 1 Jan2001

c) Must be written inEnglish

a) Study is notpublished in a peerreviewed journal

b) Study is publishedbefore 1 Jan 2001

c) Study is not writtenin English

To ensure a level ofaccountability and highquality the research shouldhave withstood scrutiny frompeers within the field.

Since much of the work lieswithin educational policy, anattempt has been made tolocate relatively recentresearch. Moreover, the NoChild Left Behind (2001)movement set a requirementfor US schools to useevidence-based strategies topromote studentachievement.

The resources are notavailable to translate articlesnot written in English

3) Type ofStudy /Intervention

a) Must be anempirical study andcontain anintervention aroundlanguage or talk.

b) Must containvariables reporting apre- and post-outcome measurearound language

a) Study does notreport primaryempirical data anddoes not contain anintervention aroundlanguage or talk.

b) Study does notcontain variablesreporting a pre- andpost- outcomemeasure around

To allow for a faircomparison and reviewbetween studies.

To ensure the effectivenessof language interventions onliteracy/language outcomesare reviewed.


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Criterion Inclusion criteria Exclusion criteria Rationaleand/or literacy.

c) Must be abetween-group studythat utilises someform of control orcomparison groupregarding languageinterventions.

language and/orliteracy.

c) Study is not abetween-group studythat utilises someform of control orcomparison groupregarding languageinterventions.

Typically, withoutintervention, teachers wouldexpect to accomplish aneffect between d = 0.15 andd = 0.40 in a typical year(Hattie, 2009 p.20) and thusa control group is required tomeasure the effect theintervention has had, whencompared with nointervention.

4) Outcomes a) Must report onoutcome measures oflanguage and/orliteracy skillsincluding writing andreading attainment.

a) Study does notreport on outcomemeasures oflanguage and/orliteracy skillsincluding writing andreading attainment.

Evidence indicates that orallanguage underpins literacyskills and this review isexamining the effectivenessof language interventions indeveloping such skills(Scarborough, 2001).


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Figure 1. Flow chart representation of full literature search conducted on 19 January 2016.

Total records identified throughelectronic databases (PsycINFO,Web of Science & ERIC)

N = 145

Excluded due to duplicates

N = 60

Abstracts Screened

N = 85

Full Text Articles Screened

N = 24

Excluded with reasons:

N = 76

Criteria 1: N = 19

Criteria 2: N = 14

Criteria 3: N = 30

Criteria 4: N = 0

Remaining Articles

N = 9

Records identified throughancestral search conducted

on remaining studies

N = 15

Studies included in Synthesis

N = 5

Excluded with reasons:

N = 19

Criteria 1: N = 2

Criteria 2: N = 2

Criteria 3: N = 11

Criteria 4: N = 3


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Table 3

Studies included for critical analysis after inclusion criteria applied during systematicliterature search

Included StudiesMcCabe, A., Boccia, J., Bennett, M. B., Lyman, N., & Hagen, R. (2010). Improvingoral language and literacy skills in preschool children from disadvantagedbackgrounds: Remembering, writing, reading (RWR). Imagination, Cognition andPersonality, 29(4), 363-390.

McIntosh, B., Crosbie, S., Holm, A., Dodd, B., & Thomas, S. (2007). Enhancingthe phonological awareness and language skills of socially disadvantagedpreschoolers: An interdisciplinary programme. Child Language Teaching andTherapy, 23(3), 267-286.

Snow, P. C., Eadie, P. A., Connell, J., Dalheim, B., McCusker, H. J., & Munro, J.K. (2014). Oral language supports early literacy: A pilot cluster randomized trial indisadvantaged schools. International journal of speech-language pathology, 16(5),495-506.

Wasik, B. A., Bond, M. A., & Hindman, A. (2006). The effects of a language andliteracy intervention on Head Start children and teachers. Journal of EducationalPsychology, 98(1), 63.

Zevenbergen, A. A., Whitehurst, G. J., & Zevenbergen, J. A. (2003). Effects of ashared-reading intervention on the inclusion of evaluative devices in narratives ofchildren from low-income families. Journal of Applied Developmental Psychology,24(1), 1-15.

Comparison of selected studies

The included studies were summarised in Table 4 and were evaluated using Gough’s (2007)

Weight of Evidence (WoE) framework which uses three categories to assess the studies:

methodological quality (WoE A), methodological relevance (WoE B) and relevance to the

research question (WoE C). Scores on each dimension were given equal weight and

averaged to find an overall weight of evidence – WoE D. The studies were coded for quality

using Gersten et al.’s (2005) criteria for evaluating evidence and completed coding protocols

are in Appendix B. The methodological relevance and appropriateness of the study were

weighted according to criteria described in Appendices C-F. For an overview of the ratings

received by each study, see Table 5.


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Table 4

Summary mapping key information of selected studies for comparison

Author StudyType

GeographicalDistribution

Age ofParticipants

Other relevantcharacteristics ofparticipants

Intervention investigated Context ofintervention

Outcomevariablesmeasured

McCabe, etal. (2010)

RCT United States ofAmerica

Mean age atpre-testing: 4years 7.5months.Mean age atpost testing:5 years 1.5months.

N = 48(28 Int. , 20 Control)27 Males & 21 Females23 Asian, 12 Hispanic,11 Caucasian & 2Mixed race

Intervention school:75.5% received FSM40% had EAL17.5% had SEN

Control Schools:65% / 68.9% FSM54.7% / 29.6% EAL14.4% / 18.6% SEN

Remembering, Writing,Reading (RWR) program.

This focuses on developingmany aspects of orallanguage through dictation ofpersonal narratives with anadult.

Children pairedwith a traineduniversity studentweekly for 20minutes over 26weeks.

ReceptiveVocabulary viaPeabody PictureVocabularyTest (PPVT-III)

Production of Oralpersonal narrative

Teacher Rating ofOral LanguageLiteracy (TROLL)

McIntosh etal. (2007)

RCT A low SES areain Queensland,Australia, basedon census data.

Mean age: 4years 9months, andranged from4 years 5months & 5years 1month)

N = 9752 boys & 45 girlsOne child EALOne child had hearingimpairment.One child had cerebralpalsy

A personalised interventionplanned by a Speech andLanguage Therapist whichincluded a PhonologicalAwareness programmefollowed by a LanguageProgramme(involving storytelling,roleplay, categorization tasks,barrier games, recallingstories and followingdirections).

Delivered towhole class by anexperiencedpreschool teacher5 days a fortnight.

Three languageactivities for eachbook and wasdistributedthroughout theday alongside thecurriculum.

Language skills viathe Quick Test ofLanguage


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Author StudyType


Age ofParticipants




Snow et al.(2014)

RCT A low SES areain Victoria,Australia

Notstipulated.Childrenwere in theirfirst twoyears ofschool andprimarilywere in anEarly Yearsclassroom.

14 schools (8intervention, 6 control)N = 1254 (602intervention, 652control)

29.6% receivededucationalmaintenance allowance5.4% received disabilityfunding1.6% had Aboriginalbackgrounds22.8% had EAL

The Oral LanguageSupporting Early Literacy(OLSEL) Project consisted of6 days of teacher andleadership training deliveredby language experts.

This included training in theICPALER (Ideas-Conventions-Purposes-Abilityto Learn-Expression andReception) Framework andcovered 4 language domains:phonemic awareness;vocabulary knowledge;awareness and application ofstory grammar; andcomprehension and use oflonger sentences.

By increasingteachersknowledge andskills around oralcompetence thiswould translateinto improvedteaching andsignificant gainsin their languageand readingability.

Oral Language viaa) Test ofLanguageDevelopment(TOLD)b) Story grammaranalysisc) RenfrewLanguage ScalesBus Story Testd) the SutherlandPhonologicalAwareness Test.

Reading attainmentvia ReadingProgress Test

Wasik et al.(2006)

RCT A high povertyneighbourhoodin United Statesof America

Mean age: 3years 10months(ranging from2 years 8months to 4years 10months)

Two Head StartSchools.16 Teachers (10intervention, 6 control)N = 207 (139intervention, 68 control)99% chn were AfricanAmerican

Oral Language trainingincluding the use of discoursestrategies and modelling richlanguage.

Book reading training.

9 month periodimplementeddaily inclassroom.Book reading:whole classformat (18-20children) withteacher andassistant.Activities ingroups of 3-5children.

Receptive andexpressiveVocabulary viaPPVT-III &EOWPVT-III.

Teacher’s level ofimplementation ofthe interventionstrategies


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Author StudyType


Age ofParticipants




Zevenbergenet al. (2003)

RCT A high povertyneighbourhoodon Long Island,New York,United States ofAmerica

Mean Age at:- pre testing4 years 4months.- post testing– 5 years

16 classrooms fromfour Head Start Centres- 3 full day, 13 half dayN = 12371 intervention, 52control53% male, 47% female41% African American325 Caucasion27% Latino/Latina

Shared Reading – aninteractive reading techniquecalled dialogic reading

30 weekinterventionconducted inclassrooms (andsome homes).Delivered byteachers togroups of 3-5children at least3x per week.

Narrative skills,with a focus on theinclusion ofevaluativeinformation viaadapted RenfrewLanguage ScalesBus Story Test

N = number of participants, M = male, F = female, FSM = Free School Meals, SEN = Special Educational Needs, EAL = English as an

Additional Language


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Table 5.

Weight of Evidence Awarded to Each Study

WoE A:Quality of

Methodology

WoE B:Relevance ofMethodology

WoE C:Relevance of

Evidence

WoE D:Overall weight

of evidence

McCabe, et al.(2010)

Medium2

Medium2

High3

Medium2.3

McIntosh et al.(2007)

Low1

Medium-Low1.3

Low1

Low1.1

Snow et al.(2014)

High3

Medium-Low1.7

High3

High2.6

Wasik et al.(2006)

High3

Medium-High2.3

Medium2

Medium2.4

Zevenbergen etal. (2003)

Low1

Medium-low1.7

Medium2

Low1.6

Participants

Two studies occurred in Australia and three in North America. McIntosh et al.’s

(2007) participants attended a preschool identified in a low SES area based on census data

(Australian Bureau of Statistics, 2003) whilst Snow et al. (2014) selected their participants

across 14 schools. These schools were also identified as being situated in a low SES area

using the Socio Economic Indexes for Areas (Australian Bureau of Statistics, 2003). In

addition, Snow et al. (2014) identified children in receipt of Educational Maintenance

Allowance as being particularly economically disadvantaged and this comprised 29.6% of

the sample. McCabe et al.’s (2010) intervention sample came from a school where 75.5% of

children received Free School Meals (FSM), which indicated low income. The other studies,

Wasik et al. (2006) and Zevenbergen et al. (2003) both took their samples from Head Start

centres, which serve high poverty children and their eligibility to attend is largely income-

based (Wasik et al., 2006). The proportion of participants from low-income families and the

method for their identification was considered when calculating WoE B.

The number of participants sourced varied between studies ranging from 48 children

(McCabe et al., 2010) to 1254 (Snow et al., 2014). To establish whether the studies had


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sufficient samples a power analysis was conducted. Previous literature of this nature,

including meta-analyses, found average effect sizes of d = 0.47 (Fricke, Bowyer‐Crane,

Haley, Hulme, & Snowling, 2013) and d = 0.27 (Law, Garrett, & Nye, 2004), which were

interpreted as small to medium effect sizes (Cohen, 1988). Therefore, when determining if

the studies in the review had sufficient participants to yield statistical power, a small to

medium effect size was considered along with 80% power and an alpha level of 0.05. Only

one study had a sufficiently large sample size to detect a small size effect (Snow et al.,

2014), however all but two of the studies (McCabe et al., 2010; McIntosh et al., 2007) were

deemed to have a sufficiently large sample to detect medium size effects.

All studies (except Snow et al., 2014) provided information about the ages of the

participants, who were all of preschool age (3-5 years). Snow et al. (2014) sourced

participants in their first two years of school and thus we cannot be sure of the exact age of

the children.

Three studies specified the proportion of their sample who were learning English as

an Additional Language (EAL) and who had Special Educational Needs (SEN). This is

significant because children with EAL and other educational needs may require differentiated

resources to learn language (Gibbons, 2002) and thus this may have impacted the size of

the effect of the intervention which may reflect the child’s additional needs as opposed to the

language intervention.

Design

All studies used a randomised controlled design and collected pre and post

measures of the intervention and comparison groups. All studies used a no-intervention

control group, which was mostly because they were class-based interventions.

Both McCabe, et al. (2010) and Wasik et al. (2006) used two schools, one as the

comparison and one as the intervention group. The benefits of this was that it avoids

exposure of the control groups to any part of the experimental condition, which could lead to

a confounding variable. In another study, Zevenbergen et al.’s (2003) sample comprised 16


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classrooms across four schools and classrooms were randomly allocated to either

intervention or control. McIntosh et al. (2007) used one school, and randomly assigned

children to two classes, an intervention class and a control class. The control class was

chosen on the basis that the teacher was imminently taking maternity leave and a

permanent replacement teacher had not been found. This created a confounding variable in

the results; supply teachers often lack knowledge about the classroom environment and the

children, which can lead to inappropriately pitched work (Trotter & Wragg, 1990). The results

of the control group may have been compounded by this change, regardless of them not

receiving the intervention and is reflected in this study’s low weighting. Snow et al. (2014)

employed a multi-stage sampling process where 14 schools were randomly allocated to

receive intervention or be controls. Stratification ensured similar representations of schools

in each group. Within the samples they were further split into Stream A, assessing oral

language and reading progress, and Stream B, assessing reading only. This enabled a

deeper analysis of the impact of the intervention and is reflected in this study’s high overall

weighting.

Three studies (McCabe et al., 2010; Snow et al., 2014; Wasik et al., 2006) reported

attrition rates, which were less than 30%, giving them a higher weighting. Reasons behind

the missing data was mostly due to child absence or moving schools. There was no

evidence in any of the studies to suggest that attrition was due to aspects of the intervention.

Characteristics of the Interventions

The quality of the intervention was considered against factors considered important

by Law and Harris (2006) when evaluating interventions that aim to promote communication

skills in socially disadvantaged children and was reflected in WoE B and C.


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Breadth of Content - The interventions differed across the studies with varying emphases.

McCabe et al. (2010) aimed to promote verbal communication using the child’s own

productions. McIntosh et al. (2007) utilised a personalised intervention drawn up by SALT. In

contrast, Snow et al. (2014), Wasik et al. (2006) and Zevenbergen et al. (2003) all targeted

teacher’s professional development. Zevenbergen et al.’s (2003) study trained both parents

and teachers and thus the involvement of home reduced the relevance, and thus weighting,

of this study. The manualisation and appropriateness of each intervention was also

considered and different weightings were allocated when rating the WoE C.

Group Size – Group size varied with individual (McCabe et al., 2010); small group (3-5

children) (Wasik et al., 2006; Zevenbergen et al., 2003) and whole class intervention (Snow

et al., 2014). This impacts the feasibility of the intervention as whole class programmes

would usually be carried out by the main class teacher, whereas small group or individual

interventions would require additional staff and thus this was considered when drawing

conclusions from the review.

Time / Length of intervention - The programme intensity varied across studies ranging from

weekly 20 minute sessions over a 26-week period (McCabe et al., 2010) to being embedded

daily in the curriculum and continuing over 18 months (Snow et al., 2014).

Fidelity

Evidence of whether the intervention was carried out correctly is considered by both

WoE A and B, with Wasik et al. (2006) scoring particularly highly. This study adopted a

coaching model whereby the intervention teachers received monthly training, observations

and feedback. McIntosh et al. (2007) and Snow et al. (2014) received moderate weighting in

this category as they utilised some elements to support fidelity. However it was not clear in

these studies whether the intervention was being explicitly monitored for fidelity, which


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appears to be implied rather than formally identified. Both McCabe et al. (2010) and

Zevenbergen et al. (2003) lacked fidelity thereby lowering their rating in WoE A and B.

Outcome Measures, including effect size interpretations

The outcomes and effectiveness were compared across the studies, which proved

difficult due to the variation between the methods employed. Most papers provided effect

sizes, and where these were not reported (McIntosh et al., 2007; Snow et al., 2014) the data

available was used to calculate an estimate of effect size using the Campbell Collaboration

Calculator (n.d.), and was interpreted according to criteria from Cohen (1988), as indicated

in Table 6.

Table 6.

Interpretations of Effect Sizes (Cohen, 1988)

Type of effect size Small Medium Large

Partial eta square 0.01 0.06 0.14Cohen’s d 0.2 0.5 0.8


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Table 7

Summary of outcomes and effect sizes

Study SampleSize

Outcome measures Significant? Effect size Effect sizeinterpretation

OverallWoE D

McCabe, etal. (2010)

N = 48Receptive language - PPVT-IIITROLL oralTROLL writingTROLL readingNarrative Quality

Year 1 Year 2p = .036 p = .034p = .006 ns (p = 355)ns (p = .098) ns (p = .162)ns (p = .01) ns (p = .165)p = .042 p < 0.001

Year 1 / Year 2η2 = 0.098 η2 = 0.10η2 = 0.16

η2 = 0.09 η2 = 0.26

LargeLarge

Large

Medium

McIntosh etal. (2007)

N = 97 Test of Languagea) Post testb) 3 month Follow up

nsp < .05 d = 0.43 Small-Medium

Low

Snow et al.(2014)

N = 1254 a) TOLD picture vocabularyb) TOLD syntactic understandingc) Story Grammar omnibusd) Narrative story grammare) Narrative syntactic analysisf) Reading Progress Test

p = 0.002p <0.001p <0.001nsnsp <0.001

d = 0.27d = 0.42d = 0.33

d = 0.62

SmallSmall-Medium

Small

Medium

High

Wasik et al.(2006)

N = 207 Receptive language - PPVT-IIIExpressive language -EOWPVT-III

p <0.001

p <0.001

d = 0.73

d = 0.44

Medium-Large

Small-Medium

Medium

Zevenbergenet al. (2003)

N = 123 Narrative Analysisa) Character statesb) Dialoguec) Causal statements

p <0.05p <0.01ns

d = 0.48d = 0.50

Small-MediumMedium

Low


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Table 7 summarises the outcomes and effect sizes of language and/or literacy gain.

Outcome measures have been categorised according to the area of language measured:

receptive language (including receptive vocabulary), expressive language, narrative,

grammar, reading and writing.

Receptive language (includes receptive vocabulary) - Both McCabe et al. (2010) and Wasik

et al. (2006) employed the Peabody Picture Vocabulary Test (PPVT-III; Dunn & Dunn, 1997)

designed to assess receptive vocabulary and has been demonstrated to be both valid and

reliable. Both studies reported medium or large effects on the children’s receptive

vocabulary. Moreover, Snow et al. (2014) measured receptive vocabulary using the Picture

Vocabulary subtest of the Test of Language Development: Primary – Fourth Edition (TOLD-

4; Newcomer & Hammill, 2008), which is designed to measure a child’s understanding of the

meaning of spoken English words, and found a small effect. Together, with their medium-

high WoE ratings, these studies show encouraging findings which suggest language

interventions can have a positive effect on children’s vocabulary.

Expressive language - McCabe et al. (2010) employed the Teacher Rating of Oral Language

(TROLL) (Dickinson, McCabe, & Sprague, 2003) which has demonstrated strong internal

consistency and correlates with other assessments of oral language (McCabe et al., 2010).

Its acknowledgment of a child’s performance over time in a classroom means that it is less

susceptible to children’s unusual conditions e.g. illness. In this study, a large effect was

reported suggesting the language intervention had improved the children’s expressive

language in these areas. Wasik et al. (2006) employed the Expressive One-Word Picture

Vocabulary Test (3rd ed.; EOWPVT–III; Brownell, 2000) to measure changes in expressive

language. A small-medium effect was reported with a significance level much smaller than p

= 0.05, suggesting that the observed effects were unlikely to have occurred by chance. The

final study to measure expressive language specifically, was Snow et al. (2014) who carried


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out the Syntactic Understanding subtest of TOLD which aims to measure children’s

comprehension of the meaning of sentences. They reported a small-medium effect with a

significance below p = 0.05 and alongside the study’s high overall WoE rating, this is highly

promising and relevant to answering the review question. Taking all of these outcomes into

consideration it would suggest the interventions led to a statistically significant improvement

in children’s expressive language skills.

McIntosh et al. (2007) used a standardised Quick Test of Language (McIntosh &

Liddy, 2006) which is a combined measure of receptive and expressive vocabulary. The

measures carried out post intervention were not statistically significant however the

measures completed at follow up, three months later, reported a small-medium effect. The

study interpreted this as possibly being due to the need for children to spend time

consolidating and generalising language, however, with its low overall WoE rating these

results were not considered as particularly applicable in answering this review question.

Narrative - Three studies carried out measures of narrative skills of the children. The study

with the highest overall WoE rating (Snow et al., 2014) reported no significant effect on the

children’s narrative syntactic analysis nor their narrative story grammar. Conversely,

McCabe, et al. (2010) who achieved a medium overall WoE rating, found a large effect on

the narrative quality of children post intervention. This may reflect the fact that the

intervention that McCabe et al. (2010) used was primarily focused on the dictation and

extension of the children’s oral personal narratives and thus one must question the extent to

which this improvement would generalise to other literacy skills. Zevenbergen et al. (2003)

also conducted a narrative analysis and broke down the measures into the inclusion of three

aspects, character states, dialogue and causal statements. This study found small-medium

effects in the inclusion of character states and dialogue but not causal statements. Given this

study’s low overall WoE rating, these results will not be considered as having a dramatic

contribution to answering this review question.


20

Grammar - Snow et al. (2014) was the only study to measure the children’s grammar and

found a small, statistically significant effect.

Literacy gain through reading and writing measures - Snow et al. (2014) conducted reading

progress tests and reported a medium effect. The significance level was much lower than p

= 0.05 and alongside the study’s high overall WoE rating, this finding is highly applicable to

answering our review question. However, McCabe et al. (2010) also carried out teacher

ratings of children’s reading and writing skills and found no statistically significant effects.

This study had a medium overall WoE rating and this finding is also very relevant in

answering the review question

Conclusion

This review evaluated five studies that provided school-based oral language interventions to

children from low-income families, mostly in preschools. All studies used randomised

controlled trials, a methodology widely recognised as the most rigorous form of study

available to test the impact of an intervention (Akobeng, 2005). Their findings largely

indicated a trend towards a positive effect of such language interventions on improving

children’s receptive and expressive language skills, however this improvement was not

consistently reflected in other literacy skill measures, such as reading, with two studies

reporting conflicting findings.

Close analysis using coding protocols and the WoE Framework revealed the

variance in methodology employed by the studies. Only Snow et al. (2014) achieved a high

overall WoE, indicating that it employed suitable methodology, which was of high quality and

highly relevant in answering the current review question. The remaining studies were

deemed to be of medium or low overall quality. Therefore, when considering the findings it is

important to recognise the limitations of these studies. There were a number of factors that

made comparisons between the studies difficult including: different measurement tools,


21

varying intensity levels of the intervention (time, breadth of content), and inconsistent

reporting of fidelity. Therefore, whilst promising results did exist with regard to the effect of

the language interventions on literacy skills of children from low-income families, the lack of

controlled variables in the studies make it difficult to determine the most important element of

the intervention in producing the effect.

Despite the methodological weaknesses, this review finds promising support for

school-based language interventions in developing language and possibly literacy skills in

socio-economically disadvantaged children, although the long-term impact remains unclear.

A number of factors would need to be considered should this type of intervention be

recommended to schools, which are outlined below.

Recommendations

Based solely on evidence from the selected studies, it would be appropriate for

practitioners to recommend language interventions to preschools to support the language

development of socio-economically disadvantaged children. The research offers promising

results to suggest an improvement in both receptive and expressive language immediately

after the intervention. However there remains a lack of information on the wider and long-

term effects of such interventions. Since there are few studies looking at the use of such

interventions with this cohort and the fact the intensity and breadth of the interventions vary

so much, any recommendations should be made with caution.

Most of the studies encompassed elements of developing teachers’ professional

development around encouraging language in the classroom through techniques such as

interactive discourse or dialogic reading, which supports the movement towards a more

consultative approach between school staff and SALT. Three studies which had this as a

key element found medium to large effects (McCabe et al., 2010; Wasik et al., 2006;

Zevenbergen et al., 2003). Moreover, Snow et al. (2014), who found a medium effect on

reading progress, adopted a more generalised version of teacher professional development

including improving vocabulary knowledge, story grammar, and comprehension of complex


22

sentences. Consultation with SALT to support staff training in these areas could be very

implementable, and would build capacity to improve language skills in socio-economically

disadvantaged children. After the initial training, it simply requires time for enhanced adult-

child interaction, which could be implemented flexibly, either to a whole class e.g. during

story time or during a one-to-one reading session.

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:

Wider Measures: most measures are limited to improvements in language, however

it may be of interest to explore the wider impact of the interventions, such as in

reading and writing.

Follow up Measures: Further research should establish whether the effects are

sustained over time through follow up measures. Henning, McIntosh, Arnott, and

Dodd (2010) tested the participants from McIntosh et al.’s (2007) sample three years

after intervention and found no significant differences between those who had

received the intervention in preschool and those who had not. This indicated that

while generating short-term positive effects, language intervention in preschool might

not enhance socially disadvantaged children’s language and literacy achievement in

the long term.

Range of Participants: It may be of interest to conduct further research on the

efficacy of language interventions on older primary-age children, such as those in the

infants or juniors.

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30

Appendix A – Excluded Studies

Studies excluded at abstract screen with rationale based on inclusion/exclusion criteria

Study Reason forexclusion

Kim, D., Park, Y., & Lombardino, L. J. (2015). Rapid automatizednaming, word-level reading, and oral reading fluency in first-gradeKorean readers at risk for reading difficulties. Asia PacificEducation Review, 16(3), 447-459.

3a

Elwér, Å., Gustafson, S., Byrne, B., Olson, R. K., Keenan, J. M., &Samuelsson, S. (2015). A retrospective longitudinal study ofcognitive and language skills in poor reading comprehension.Scandinavian journal of psychology, 56(2), 157-166.

3a

Permenter, D. A. (2013). The effects of pre-kindergartenparticipation on reading achievement among English languagelearners who are socioeconomically disadvantaged in grades 1, 2and 3 in a large urban public school district in North Texas.TEXAS A&M UNIVERSITY-COMMERCE.

2a

Duff, F. J., Hulme, C., Grainger, K., Hardwick, S. J., Miles, J. N., &Snowling, M. J. (2014). Reading and language intervention forchildren at risk of dyslexia: a randomised controlled trial. Journalof Child Psychology and Psychiatry, 55(11), 1234-1243.

1b

Colmar, S. H. (2014). A parent-based book-reading interventionfor disadvantaged children with language difficulties. ChildLanguage Teaching and Therapy, 30(1), 79-90.

1c

Rahn, N. L. (2013). A comparison of word learning in 3-year-oldchildren at-risk for language and literacy difficulties in twoconditions: dialogic reading and activity-based intervention(Doctoral dissertation, University of Minnesota).

2a

Fry-Bowers, E. K. (2012). The Impact of Maternal Health Literacyon Structures, Interpersonal Processes and Outcomes ofAmbulatory Care for Low-Income Latino Children.

2a

Sparks, A., & Reese, E. (2013). From reminiscing to reading:Home contributions to children’s developing language and literacyin low-income families. First Language, 33(1), 89-109.

1c

Guzman-Orth, D. A. (2012). When is an English language learnernot an English language learner? Exploring individual differencesin developmental language and literacy acquisition for at-risklearners: A latent transition approach. University of California,Santa Barbara.

2a

Petersen, D. B., & Gillam, R. B. (2013). Accurately predictingfuture reading difficulty for bilingual Latino children at risk forlanguage impairment. Learning Disabilities Research & Practice,28(3), 113-128.

3a

Fry-Bowers, E. K., Maliski, S., Lewis, M. A., Macabasco-O’Connell, A., & DiMatteo, R. (2013). Health literacy andinterpersonal interactions as predictors of maternal perception ofambulatory care for low-income, Latino children. Patient educationand counseling, 91(2), 213-220.

3a

Luo, Y. H., Snow, C. E., & Chang, C. J. (2011). Mother-child talkduring joint book reading in low-income American and Taiwanesefamilies. First Language, 0142723711422631.

1c


31

Erdos, C. (2011). Predicting Language and Literacy Outcomes ofTypically-Developing and At-risk English-speaking ElementaryStudents in French Immersion Programs. McGill UniversityLibrary.

2a

Pitchlyn, C. L. (2010). Longitudinal Analysis of Relations amongBehavior Problems, Language, and Early Literacy GrowthTrajectories for Young Children At-Risk for Significant BehaviorProblems.

2a

Tardáguila-Harth, J. M. (2007). Assessing the effects of dialogicreading on the oral language skills of migrant preschoolers at riskfor reading difficulties (Doctoral dissertation, University of Florida).

2a

Illmer Craciun, D. (2011). The Relationships Between HomeSupport For Language And Emergent Literacy In Low-IncomeFamilies, Mother's Education And Immigrant Status, AndChildren's Language And Emergent Literacy Development AtKindergarten Entry.

2a

Vagh, S. B. (2009). Learning at Home and at School: ALongitudinal Study of Hindi Language and Emergent LiteracySkills of Young Children from Low Income Families in India(Doctoral dissertation, Harvard Graduate School of Education).

2a

Stechuk, R. (2008). Predicting language and early literacyoutcomes in low-income children: A structural equation modelingapproach. George Mason University.

2a

Moody, A. K. (2007). Engagement and communication duringshared storybook reading: A comparison of electronic andtraditional books for preschoolers who are at-risk. ProQuest.

2a

Duursma, A. E. (2007). Parental bookreading in low-incomefamilies: Differences and similarities between fathers and mothersin frequency and style of reading and the impact on children'slanguage and literacy development (Doctoral dissertation,ProQuest Information & Learning).

2a

Ming, K. (2007). The Effects of a Fluency Intervention on the OralReading Fluency of First Grade Students at Risk for ReadingFailure (Doctoral dissertation, Florida Atlantic University).

2a

McArthur, G. M., & Hogben, J. H. (2012). Poor auditory taskscores in children with specific reading and language difficulties:some poor scores are more equal than others. Scientific Studiesof Reading, 16(1), 63-89.

3a

Swanson, H. L., Orosco, M. J., & Lussier, C. M. (2012). Cognitionand literacy in English language learners at risk for readingdisabilities. Journal of educational psychology, 104(2), 302.

3a

Paleologos, T. M., & Brabham, E. G. (2011). The effectiveness ofDIBELS oral reading fluency for predicting readingcomprehension of high-and low-income students. ReadingPsychology, 32(1), 54-74.

3a

Nation, K., Cocksey, J., Taylor, J. S., & Bishop, D. V. (2010). Alongitudinal investigation of early reading and language skills inchildren with poor reading comprehension. Journal of ChildPsychology and Psychiatry, 51(9), 1031-1039.

3a

Loftus, S. M., Coyne, M. D., McCoach, D. B., Zipoli, R., & Pullen,P. C. (2010). Effects of a supplemental vocabulary intervention onthe word knowledge of kindergarten students at risk for languageand literacy difficulties. Learning Disabilities Research & Practice,25(3), 124-136.

1b


32

Kim, J. S., & Guryan, J. (2010). The efficacy of a voluntarysummer book reading intervention for low-income Latino childrenfrom language minority families. Journal of EducationalPsychology, 102(1), 20.

1c

Loeb, D. F., Gillam, R. B., Hoffman, L., Brandel, J., & Marquis, J.(2009). The effects of Fast ForWord Language on the phonemicawareness and reading skills of school-age children withlanguage impairments and poor reading skills. American Journalof Speech-Language Pathology, 18(4), 376-387.

1d

Gyovai, L. K., Cartledge, G., Kourea, L., Yurick, A., & Gibson, L.(2009). Early reading intervention: Responding to the learningneeds of young at-risk English language learners. LearningDisability Quarterly, 32(3), 143-162.

3a

Wang, C., Porfeli, E., & Algozzine, B. (2008). Development of oralreading fluency in young children at risk for failure. Journal ofEducation for Students Placed at Risk, 13(4), 402-425.

3a

Fletcher, K. L., Cross, J. R., Tanney, A. L., Schneider, M., &Finch, W. H. (2008). Predicting language development in childrenat risk: The effects of quality and frequency of caregiver reading.Early Education and Development, 19(1), 89-111.

1c

Nation, K., Snowling, M. J., & Clarke, P. (2007). Dissecting therelationship between language skills and learning to read:Semantic and phonological contributions to new vocabularylearning in children with poor reading comprehension.International Journal of Speech-Language Pathology, 9(2), 131-139.

3a

Catts, H. W., & Weismer, S. E. (2006). Language deficits in poorcomprehenders: A case for the simple view of reading. Journal ofSpeech, Language, and Hearing Research, 49(2), 278-293.

3a

Hammer, C. S., & Miccio, A. W. (2006). Early Language andReading Development of Bilingual Preschoolers From Low‐Income Families. Topics in Language Disorders, 26(4), 322-337.

3a

Bernhard, J., Cummins, J., Campoy, F., Ada, A., Winsler, A., &Bleiker, C. (2006). Identity texts and literacy development amongpreschool English language learners: Enhancing learningopportunities for children at risk for learning disabilities. TheTeachers College Record, 108(11), 2380-2405.

1b

Viholainen, H., Ahonen, T., Lyytinen, P., Cantell, M., Tolvanen, A.,& Lyytinen, H. (2006). Early motor development and laterlanguage and reading skills in children at risk of familial dyslexia.Developmental Medicine & Child Neurology, 48(5), 367-373.

1b

Marthinussen, P. J., & Van der Merwe, M. F. (2015). An adjustedprogramme to improve phonological and phonemic awareness inearly reading of Grade 1 learners in a language-poorenvironment. Per linguam-a journal of language learning, 31(2),53-78.

3a

Fry-Bowers, E. K., Maliski, S., Lewis, M. A., Macabasco-O'Connell, A., & DiMatteo, R. (2013). The association of healthliteracy, social support, self-efficacy and interpersonal interactionswith health care providers in low-income Latina mothers. Journalof pediatric nursing, 29(4), 309-320.

3a

Hooper, S. R., Costa, L. J. C., McBee, M., Anderson, K. L., Yerby,D. C., Childress, A., & Knuth, S. B. (2013). A written languageintervention for at-risk second grade students: a randomized

3a


33

controlled trial of the process assessment of the learner lessonplans in a tier 2 response-to-intervention (RtI) model. Annals ofdyslexia, 63(1), 44-64.Kim, B. J., Hwang, M., & Choi, K. S. (2013). Word Processing ofChildren with Poor Reading Comprehension during an On-lineVerbal Analogy Task. Communication Sciences & Disorders,18(3), 269-276.

3a

Eun-Jung, S. (2013). The Effects of the Five W's and One HSentence Writings & Oral Presentation Strategy on the SentenceWriting Ability and Oral Presentation Skills for the Students atRisk. Journal of Intellectual Disabilities, 15(4), 233-254.

1d

Stein, A., & Rosemberg, C. R. (2012). Collaboration networks infamily literacy situations with preschool children: A study with poorurban population from Argentina.Interdisciplinaria, 29, 95-108.

3a

Lee, J. Y., Divaris, K., Baker, A. D., Rozier, R. G., Lee, S. Y. D., &Vann Jr, W. F. (2011). Oral health literacy levels among a low‐income WIC population. Journal of public health dentistry, 71(2),152-160.

3a

Mendelsohn, A. L., Huberman, H. S., Berkule, S. B., Brockmeyer,C. A., Morrow, L. M., & Dreyer, B. P. (2011). Primary carestrategies for promoting parent-child interactions and schoolreadiness in at-risk families: the Bellevue Project for EarlyLanguage, Literacy, and Education Success. Archives ofpediatrics & adolescent medicine, 165(1), 33-41.

1c

Liu, P. D., McBride-Chang, C., Wong, A. M. Y., Tardif, T., Stokes,S. F., Fletcher, P., & Shu, H. (2010). Early oral language markersof poor reading performance in Hong Kong Chinese children.Journal of Learning Disabilities, 43(4), 322-331.

3a

Park, C. H., & Kim, M. S. (2010). The Longitudinal Effects of anEarly Storybook Reading Intervention Program on theImprovement of First Graders' Language Abilities in Low-incomeFamilies. Korean Journal of Child Studies, 31(3), 117-138.

3a

Cirino, P. T., Vaughn, S., Linan-Thompson, S., Cardenas-Hagan,E., Fletcher, J. M., & Francis, D. J. (2009). One-year follow-upoutcomes of Spanish and English interventions for Englishlanguage learners at risk for reading problems. AmericanEducational Research Journal, 46(3), 744-781.

1b

Rodriguez, B. L., Hines, R., & Montiel, M. (2009). MexicanAmerican mothers of low and middle socioeconomic status:Communication behaviors and interactive strategies duringshared book reading. Language, Speech, and Hearing Services inSchools, 40(3), 271-282.

1c

Flax, J. F., Realpe-Bonilla, T., Roesler, C., Choudhury, N., &Benasich, A. (2008). Using early standardized languagemeasures to predict later language and early reading outcomes inchildren at high risk for language-learning impairments. Journal oflearning disabilities.

1d

Simon, E. N. (2008). Can language and reading proficiency befollowed into the school years for infants born in poor condition?.American journal of obstetrics and gynecology, 198(2), 243.

3a

Justice, L. M., Mashburn, A. J., Hamre, B. K., & Pianta, R. C.(2008). Quality of language and literacy instruction in preschoolclassrooms serving at-risk pupils. Early Childhood Research

3a


34

Quarterly, 23(1), 51-68.Chang, Y. E., Lee, S. J., & Lee, K. Y. (2008). The Effects ofMothers' Reading and Teacher's Sensitivity and Permissivenesson 4-and 5-year-olds' Verbal and Numerical Abilities in Low-income Families-The Analysis of FACES Data in the US toDevelop Intervention Programs for Low-Income Families. Journalof the Korean Home Economics Association, 46(1), 117-129.

3a

Morfidi, E., Van Der Leij, A., De Jong, P. F., Scheltinga, F., &Bekebrede, J. (2007). Reading in two orthographies: A cross-linguistic study of Dutch average and poor readers who learnEnglish as a second language. Reading and writing, 20(8), 753-784.

1a

Vaughn, S., Mathes, P., Linan‐Thompson, S., Cirino, P., Carlson,C., Pollard‐Durodola, S., ... & Francis, D. (2006). Effectiveness ofan English intervention for first‐grade English language learners atrisk for reading problems. The Elementary School Journal, 107(2),153-180.

1b

Linan-Thompson, S., Vaughn, S., Prater, K., & Cirino, P. T.(2006). The response to intervention of English language learnersat risk for reading problems. Journal of Learning Disabilities,39(5), 390-398.

3a

Vaughn, S., Linan-Thompson, S., Mathes, P. G., Cirino, P. T.,Carlson, C. D., Pollard-Durodola, S. D., ... & Francis, D. J. (2006).Effectiveness of Spanish intervention for first-grade Englishlanguage learners at risk for reading difficulties. Journal ofLearning Disabilities, 39(1), 56-73.

1b

Parker, D. C., Zaslofsky, A. F., Burns, M. K., Kanive, R., Hodgson,J., Scholin, S. E., & Klingbeil, D. A. (2015). A Brief Report of theDiagnostic Accuracy of Oral Reading Fluency and ReadingInventory Levels for Reading Failure Risk Among Second-andThird-Grade Students. Reading & Writing Quarterly, 31(1), 56-67.

3a

McCracken, T. B. (2013). The Impact of Evidence-BasedPractices on the Oral Reading Fluency of Low-Socioeconomic-Status Elementary Students (Doctoral dissertation, IndianaUniversity of Pennsylvania).

2a

Darrow, C. L. (2009). Language and Literacy Effects ofCurriculum Interventions for Preschools Serving EconomicallyDisadvantaged Children: A Meta Analysis. Society for Researchon Educational Effectiveness.

3a

Torppa, M., Lyytinen, P., Erskine, J., Eklund, K., & Lyytinen, H.(2010). Language development, literacy skills, and predictiveconnections to reading in Finnish children with and without familialrisk for dyslexia. Journal of Learning Disabilities.

3a

van der Lely, H. K., & Marshall, C. R. (2010). Assessingcomponent language deficits in the early detection of readingdifficulty risk. Journal of learning disabilities, 43(4), 357-368.

3a

Puolakanaho, A., Ahonen, T., Aro, M., Eklund, K., Leppänen, P.H., Poikkeus, A. M., ... & Lyytinen, H. (2007). Very earlyphonological and language skills: estimating individual risk ofreading disability. Journal of Child Psychology and Psychiatry,48(9), 923-931.

3a

Speece, D. L., & Ritchey, K. D. (2005). A longitudinal study of thedevelopment of oral reading fluency in young children at risk forreading failure. Journal of Learning Disabilities, 38(5), 387-399.

3a


35

Reading, C. O. (2005). Connections between language andreading in children with poor reading comprehension. Theconnections between language and reading disabilities, 37.

1b

Nation, K., Clarke, P., Marshall, C. M., & Durand, M. (2004).Hidden Language Impairments in Children Parallels BetweenPoor Reading Comprehension and Specific LanguageImpairment?. Journal of Speech, Language, and HearingResearch, 47(1), 199-211.

1d

Morgan, L., & Goldstein, H. (2004). Teaching mothers of lowsocioeconomic status to use decontextualized language duringstorybook reading. Journal of Early Intervention, 26(4), 235-252.

1c

Limbos, M. M., & Geva, E. (2001). Accuracy of teacherassessments of second-language students at risk for readingdisability. Journal of learning disabilities, 34(2), 136-151.

1d

Savage, R., Patni, U., Frederickson, N., Goodwin, R., Smith, N., &Tuersley, L. (2005). Evaluating current deficit theories of poorreading: role of phonological processing, naming speed, balanceautomaticity, rapid verbal perception and working memory 1.Perceptual and motor skills, 101(2), 345-361.

3a

Tenenbaum, H. R., Snow, C. E., Roach, K. A., & Kurland, B.(2005). Talking and reading science: Longitudinal data on sexdifferences in mother–child conversations in low-income families.Journal of Applied Developmental Psychology, 26(1), 1-19.

1c

Carroll, J. M., & Snowling, M. J. (2004). Language andphonological skills in children at high risk of reading difficulties.Journal of Child Psychology and Psychiatry, 45(3), 631-640.

1d

Haine, R. A., & Tabors, P. O. (2001). Low-income mothers'calibrated support during their children's early oral reading.Research on child language acquisition, 1, 409-421.

1c

Moore, R., & Seeger, V. Rich Versus Poor: Family Literacy in theElementary Language Arts Curriculum. Language and LiteracySpectrum, 53.

3a

Morgan, L., & Goldstein, H. (2004). Teaching mothers of lowsocioeconomic status to use decontextualized language duringstorybook reading. Journal of Early Intervention, 26(4), 235-252.

1c

Smetana, L. (2005). Collaborative storybook reading: bringparents and at-risk kindergarten students together. ReadingHorizons, 45(4), 283.

1c

Lyytinen, P., Eklund, K., & Lyytinen, H. (2005). Languagedevelopment and literacy skills in late-talking toddlers with andwithout familial risk for dyslexia. Annals of dyslexia, 55(2), 166-192.

1d

Carroll, J. M., & Snowling, M. J. (2004). Language andphonological skills in children at high risk of reading difficulties.Journal of Child Psychology and Psychiatry, 45(3), 631-640.

1d

Studies excluded at full text screen with rationale based on inclusion/exclusion criteria. This

included the studies added from the ancestral search.

Study Reason forexclusion

Nagy, W., Berninger, V., Abbott, R., Vaughan, K., & Vermeulen, 3a


36

K. (2003). Relationship of Morphology and Other Language Skillsto Literacy Skills in At-Risk Second-Grade Readers and At-RiskFourth-Grade Writers. Journal of educational psychology, 95(4),730.Nicolopoulou, A., Cortina, K. S., Ilgaz, H., Cates, C. B., & de Sá,A. B. (2015). Using a narrative-and play-based activity to promotelow-income preschoolers’ oral language, emergent literacy, andsocial competence. Early childhood research quarterly, 31, 147-162.

3a

Han, M., Vukelich, C., Buell, M., & Meacham, S. (2014). Beatingthe odds: A longitudinal investigation of low-income dual-languageand monolingual children's English language and literacyperformance. Early Education and Development, 25(6), 841-858.

3a

Justice, L. M., McGinty, A. S., Cabell, S. Q., Kilday, C. R.,Knighton, K., & Huffman, G. (2010). Language and literacycurriculum supplement for preschoolers who are academically atrisk: A feasibility study. Language, Speech, and Hearing Servicesin Schools, 41(2), 161-178.

3a

Huffstetter, M., King, J. R., Onwuegbuzie, A. J., Schneider, J. J.,& Powell-Smith, K. A. (2010). Effects of a computer-based earlyreading program on the early reading and oral language skills ofat-risk preschool children. Journal of Education for StudentsPlaced at Risk, 15(4), 279-298.

3a

Kennedy, E., & Shiel, G. (2010). Raising Literacy Levels WithCollaborative On‐Site Professional Development in an UrbanDisadvantaged School. The Reading Teacher, 63(5), 372-383.

3a

Excluded Studies from Ancestral Search

Bowyer‐Crane, C., Snowling, M. J., Duff, F. J., Fieldsend, E.,Carroll, J. M., Miles, J., Gotz, K., & Hulme, C. (2008). Improvingearly language and literacy skills: Differential effects of an orallanguage versus a phonology with reading intervention. Journal ofChild Psychology and Psychiatry, 49(4), 422-432.

1b

Dickinson, D. K. (2011). Teachers’ language practices andacademic outcomes of preschool children. Science, 333(6045),964-967.

3a

Dockrell, J., Stuart, M., & King, D. (2006). Implementing effectiveoral language interventions in preschool settings: no simplesolutions. In J. Clegg, J. Ginsborg, & J. Ginsbourg (Eds.),Language and social disadvantage: theory into practice. (pp. 177-187). Chichester: Wiley.

4a

Hay, I., & Fielding-Barnsley, R. (2009). Competencies thatunderpin children's transition into early literacy.

3a

Hoff, E. (2006). How social contexts support and shape languagedevelopment. Developmental Review, 26(1), 55-88.

3a

Law, J. & Harris, F. (2006). The effects of intervention on thecommunication skills of socially disadvantaged children. Clegg, Jand Ginsborg, J Language and Social Disadvantage: Theory intoPractice. London: John Wiley and Sons Ltd, 122-137.

4a

Hutchinson, J., & Clegg, J. (2011). Education practitioner-ledintervention to facilitate language learning in young children: Aneffectiveness study. Child Language Teaching and Therapy, (27),151-164.

4a


37

Nancollis, A., Lawrie, B. A., & Dodd, B. (2005). Phonologicalawareness intervention and the acquisition of literacy skills inchildren from deprived social backgrounds. Language, speech,and hearing services in schools, 36(4), 325-335.

3a

Coll, C. G. (2005). Pathways to reading: The role of oral languagein the transition to reading. Developmental Psychology, 41, 428-42.

3a

O'Connor, M., Arnott, W., McIntosh, B., & Dodd, B. (2009).Phonological awareness and language intervention inpreschoolers from low socio‐economic backgrounds: Alongitudinal investigation. British journal of developmentalPsychology, 27(4), 767-782.

3a

Beitchman, J., & Brownlie, E. (2005). Language development andits impact on children’s psychosocial and emotional development.Encyclopedia on early childhood development, 1-7.

2a

van Kleeck, A., Vander Woude, J., & Hammett, L. (2006).Fostering literal and inferential language skills in Head Startpreschoolers with language impairment using scripted book-sharing discussions. American Journal of Speech-LanguagePathology, 15(1), 85-95.

1d

Henning, C., McIntosh, B., Arnott, W., & Dodd, B. (2010). Long‐term outcome of oral language and phonological awarenessintervention with socially disadvantaged preschoolers: the impacton language and literacy. Journal of Research in Reading, 33(3),231-246.

3a


38

Appendix B – Coding Protocol used for selected studies

Name of Coder: ANONYMISED

Date: 5.2.16

Full Study Reference:

McCabe, A., Boccia, J., Bennett, M. B., Lyman, N., & Hagen, R. (2010). Improving oral

language and literacy skills in preschool children from disadvantaged backgrounds:

Remembering, writing, reading (RWR). Imagination, Cognition and Personality, 29(4), 363-

390.

Intervention Name (description of study): Language Interventions

Research design: Randomised Control Trials – Group Experimentals

Type of Publication: Journal Article

Gersten et al., (2005). Quality Indicators for Group Experimental and Quasi-Experimental

Research in Special Education

Essential Quality Indicators

Describing Participants

Was sufficient information provided to determine/confirm whether the participants

demonstrated the disability(ies) or difficulties presented?

☒ Yes

☐ No

☐ N/A

☐ Unknown/Unable to Code

Were appropriate procedures used to increase the likelihood that relevant characteristics of

participants in the sample were comparable across conditions?

☒ Yes

☐ No

☐ N/A


Was sufficient information given characterizing the interventionists or teachers provided? Did

it indicate whether they were comparable across conditions?

☒ Yes

☐ No

☐ N/A


39


Implementation of the Intervention and Description of Comparison Conditions

Was the intervention clearly described and specified?

☒ Yes - 73 tokens of vocab etc

☐ No

☐ N/A


Was the fidelity of implementation described and assessed?

☐ Yes

☒ No

☐ N/A


Was the nature of services provided in comparison conditions described?

☒ Yes - standard preschool curriculum without trained student visits

☐ No

☐ N/A


Outcome Measures

Were multiple measures used to provide an appropriate balance between measures closely

aligned with the intervention and measures of generalised performance?

☒ Yes

☐ No

☐ N/A


Were outcomes for capturing the intervention’s effect measured at the appropriate times?

☒ Yes - after 6 months

☐ No

☐ N/A



40

Data Analysis

Were the data analysis techniques appropriately linked to key research questions and

hypotheses? Were they appropriately linked to the unit of analysis in the study?

☒ Yes

☐ No

☐ N/A


Did the research report include not only inferential statistics but also effect size calculations?

☒ Yes

☐ No

☐ N/A


Desirable Quality Indicators

Was data available on attrition rates among intervention samples? Was severe overall

attrition documented? If so, is attrition comparable across samples? Is overall attrition less

than 30%?

☒ Yes – 25% in year 1 and 11.3% in year 2

☐ No

☐ N/A


Did the study provide not only internal consistency reliability but also test-retest reliability and

interrater reliability (when appropriate) for outcome measures? Were data collectors and/or

scorers blind to study conditions and equally (un)familiar to examinees across study

conditions?

☐ Yes

☒ No – some elements e.g. 15% overlap of narrative scoring but not much

☐ N/A



41

Were outcomes for capturing the intervention’s effect measured beyond an immediate

posttest?

☐ Yes

☒ No – although this was done in a second paper a year later

☐ N/A


Was evidence of the criterion-related validity and construct validity of the measures

provided?

☒ Yes – under child measures

☐ No

☐ N/A


Did the research team assess not only surface features of fidelity implementation (e.g.

number of minutes allocated to the intervention or teacher/interventionist following

procedures specified), but also examine quality of implementation?

☐ Yes

☒ No

☐ N/A


Was any documentation of the nature of instruction or series provided in comparison

conditions?

☐ Yes –

☒ No – just said preschool curriculum only in abstract

☐ N/A


Did the research report include actual audio or videotape excerpts that capture the nature of

the intervention?

☐ Yes

☒ No

☐ N/A


42


Were results presented in a clear, coherent fashion?

☒ Yes

☐ No

☐ N/A


Overall Rating of Evidence: ☐ 3 ☒ 2 ☐ 1 ☐ 0


43

Appendix C: Weight of Evidence A: Criteria and Summary

Methodological Quality (WoE A)

The WoE A criteria for group experimental designs was derived from Gersten et al. (2005).

Gersten et al. (2005) proposed a set of dichotomous criteria to rate the quality of research

(either as ‘high’ quality or ‘acceptable’ quality). He acknowledged that these definitions are

tentative and as a result, this review has adapted his criteria to produce a criteria to enable

high, medium and low weightings. Where ratings fell in between, high-medium (2.5) and

medium-low (1.5) ratings were given.

To achieve a rating of 3(high) the study must meet:

To achieve a rating of 2(medium) the study mustmeet:

To achieve a rating of 1(low) the study must meet:

All but one of theEssential QualityIndicators

At least four of theDesirable QualityIndicators.

All but one of the EssentialQuality Indicators

At least two of theDesirable QualityIndicators.

All but two of theEssential QualityIndicators

At least one of theDesirable QualityIndicators.

NB: where an ‘unknown/unable to code’ is scored, this was classed as not meeting the

criteria due to insufficient information.

A summary of the ratings for Methodological Quality is given below.

Weight of Evidence A - Score and Rating

Study Mean Score Quality RatingMcCabe et al. (2010) 2 MediumMcIntosh et al. (2007) 1 LowSnow et al. (2014) 3 HighWasik et al. (2006) 3 HighZevenbergen et al. (2003) 1 Low


44

Appendix D: Weight of Evidence B: Criteria and Summary

Methodological Relevance (WoE B)

The methodological relevance to the review question is a review specific judgement about

the appropriateness of that form of evidence for answering the review question. The

following key features were identified as having particular methodological relevance:

i) Participants – this review was focusing on language interventions for typically

developing children from low-income families and thus appropriate measures should

have been taken to ensure the sample reflects this population.

i) Appropriate measures - a wider range of measures and from different sources gives

a more suitable over view of improvement in language and literacy attainment.

ii) Appropriate monitoring of the fidelity of the implementation of the intervention –Those

conducting the interventions who have received adequate training and have been

supported and monitored are likely to increase the reliability to their implementation.

The tables below sets out the criteria for Weight of Evidence B and the individual weightings

given to each study. Each weighting received against i), ii) and iii) were added together and

an average was calculated to produce the overall weighting for WoE B for each study.

Weighting DescriptionHigh (3 points) i) Most participants have been identified as being from low-

income families using strong indicators such as attending aschool in which the eligibility to attend is based on lowincome i.e. Head Start centres.

ii) Measures come from at least 2 sources e.g. teacher andchild and measures include a language assessment AND aliteracy attainment assessment

iii) Those conducting intervention received at least 3 of:Appropriate Training; observations with feedback;regular/follow up supervision

Medium (2 points) i) Most participants have been identified as being from low-income families using indicators such as receiving FreeSchool Meals or educational maintenance allowance.

ii) Measures come from at least 1 source e.g. teacher or childand measures include a language assessment AND a


45

literacy attainment assessmentiii) Those conducting intervention received at least 2 of:

Appropriate Training; observations with feedback;regular/follow up supervision

Low (1 point) i) Participants have been identified as being from low-incomefamilies using less reliable indicators such as living in adeprived neighbourhood with no other measure.

ii) Measures come from at least 1 source e.g. teacher or childand measures just one aspect of language.

iii) Those conducting intervention received at least 1 of:Appropriate Training; observations with feedback;regular/follow up supervision

Study Score for each criteria (Mean Score) and WoE B rating

McCabe et al. (2010) i) = Medium (2)

ii) = High (3)

iii) = Low (1)

(2) Medium

McIntosh et al. (2007) i) = Low (1)

ii) = Low (1)

iii) = Medium (2)

(1.3) Medium-low

Snow et al. (2014) i) = Low (1)

ii) = Medium (2)

iii) = Medium (2)

(1.7) Medium-low

Wasik et al. (2006) i) = High (3)

ii) = Low (1)

iii) = High (3)

(2.3) Medium-High

Zevenbergen et al.(2003)

i) = High (3)

ii) = Low (1)

iii) = Low (1)

(1.7) Medium-low


46

Appendix E: Weight of Evidence C: Criteria and Summary

Topic Relevance (WoE C)

This appraisal involves a review specific judgement about whether the focus of the study

contributes towards answering the review question. The following key features were

identified as being relevant to the review topic:

1) The main focus of the study will investigate the effectiveness of language

interventions on the language and literacy skills of children from low-income families.

2) Measures of both literacy (reading or writing) attainment and use of language in the

experimental group to explicitly link increased language use to the outcome gains in

literacy skills.

3) Language interventions will be well-known or described in detail so it could be

replicated or used as a framework to inform future language interventions.

Studies were weighted as having High Topic Relevance if they met all three criteria,

Medium if they met any two criteria and Low if they met one or no criteria.

Study Criteria met WoE rating

McCabe et al. (2010) 1, 2 and 3 High3

McIntosh et al. (2007) 1 Low1

Snow et al. (2014) 1, 2 and 3 High3

Wasik et al. (2006) 1 and 3 Medium2

Zevenbergen et al. (2003) 1 and 3 Medium2

Appendix F: Weight of Evidence D: Averaging Criteria

Overall Judgement (WoE D)


47

The Weight of Evidence Averaging criteria which was used to calculate WoE D is set out

below. This criteria ensured that in order to obtain a high overall WoE, the ‘high’ weighting

must have appeared at least twice in any of the previous categories.

Weight Category Numerical RatingLow 1.6 or less

Medium 1.7-2.4High 2.5 or above

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