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Evaluation of programs forimproving language and earlyliteracy skills in young children
Literature review or Sprogpakken
Aims & PurposesThe purpose o this review is to examine the research on programs and practices thataim to improve oral language and early literacy skills in young children. This review willprovide evidence concerning the efcacy o a range o programs and practices available today-care teachers. This review also aims to raise awareness among day-care teachers aboutthe range o dierent programs and practice that have been developed.
This review examined the ollowing questions:
1. Does a curriculum/systematic approach to supporting language and early literacy skillsin young children produce better outcomes than a non-curriculum/non-systematic ap-proach?Our interest in addressing this question was to examine whether available evidence
indicates whether a systematic curriculum based approach to early learning is equiva-lent, superior or inerior to individual lesson plans developed by individual day careteachers.
2. Do all curriculum/systematic approaches have equivalent outcomes or do some have abetter eect on language and early literacy skills?A large number o dierent curriculum programs have been developed (or an over-view see Table 2). We were interested in examining whether all have an equal eecton early language or literacy outcomes.
3. What specifc practices can teachers working in early day care centres use to promotelanguage and early literacy skills?
In addition to examining entire curricula, which incorporate a range o dierent prac-tices, the current review also examined specifc practices which teachers may be ableto use. In this review we examined which specifc practices produced the best out-comes on childrens language and literacy skills.
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Approach & MethodologyIn undertaking this review, it was necessary that a representative sample o intervention
studies that have examined the eectiveness o language and pre-literacy programs beidentifed. In meeting this goal, a key issue addressed was how to best fnd previous re-search. A key concern when undertaking any review is to reduce the impact o selectionbias. In the context o a systematic or traditional review, selection bias occurs when re-searchers either knowingly or unknowingly include articles that support a particular pointo view (Egger, Smith, Schneider, & Minder, 1997). In the case o evaluating interventionsand trials, this might be only including studies that report a therapeutic eect o an inter-vention. Perhaps the main challenge in undertaking reviews, particularly o interventions,is that selection bias can unintentionally occur. For example, research has shown thatthere is a publication bias towards reporting results that only show positive eects (Egger& Smith, 1998). This might mean that it can be easier to fnd studies showing positive e-ects compared to null eects leading to selection bias in the review.
In an attempt to overcome the aorementioned problems, methodologists and researchersdeveloped a more objective approach or integrating research, which is called a system-atic review (Higgins & Green, 2008). In a systematic review, the researcher/s are requiredto explicitly describe all the steps used to fnd studies, and also which criteria was usedto include or exclude studies rom their review. The steps used to describe the literaturereview process involves explicitly stating which databases were searched, the key wordsused in the databases, the years that have been searched and also how many articles wereound and which ones were included. In addition, researchers may oten contact dierentorganisations to fnd non-published studies as well.
In the pedagogical feld, a number o systematic reviews have already been been under-taken that have evaluated best practices in promoting language and early literacy skills
in young children. These systematic reviews were the starting point in which to identiypotentially useul studies or the current review. A summary o each o these reviews ispresented in Table 1.
Additional research articles or the current review were ound ollowing a literature searchundertaken at the Centre or Child Language at The University o Southern Denmark inOdense, Denmark in November 2010. In this search the PsycIno and PubMed databaseswere used to indentiy studies published between 2007 and 2010. A list o the key wordsand search strategy in this search is presented in Appendix A. This search returned a totalo 359 articles.
The systematic reviews reported in Table 1 along with the literature search undertaken atthe Centre or Child Language were used to identiy past research to be included in this
review. Once these studies were ound, inclusion criteria were applied. Applying the cri-teria was necessary to assist in synthesising and generalising the results. These criteria arenow described in turn.
Criterion 1: Intervention studies required both treatment and control groups. To be includ-ed in the review all studies examining the efcacy o dierent intervention/practices wererequired to have at least one Intervention and one Control group in a between-subjectsdesign study.
Identifying Studies
to Include in theReview
Criteria forSelecting Studies
to be Included inthe Review.
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Table1.SystematicReviewsusedtoIdentifyStudies
Au
thors
Years
Searched
Num
berostud
iesreviewed
Burger
(2010)
1990-2
010a
32
Busetal.(
199
5)
Not
stated
inpaper.
However,
studie
sse
lected
in
the
reviewwerepu
blished
between
1951-1
993.
29
Cham
bersetal.(
2010)
1960-2
010
22
Manzetal.(2
010)
1994-2
007
43
McGro
der
&H
yra
(2009)
Not
stated
inpaper.
However,
studie
sse
lected
in
the
reviewwerepu
blished
between
1997-2
007.
12
Moletal.(
2008)
1988-2
007
11
Nat
ional
Early
Literacy
Panel
(2008)
1887-2
008
234
Reeseetal.(2
010)
Nostated
inpaper.
However,s
tudiesse
lected
in
the
reviewwerepu
blished
between
1994-2
010
11
Notes:aAu
tho
rsnoteoneexcep
tion
inw
hichastu
dypu
blished
in1987was
inclu
ded.
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Criterion 2: Participants were required to be randomly allocated to treatment and controlgroups. The second criterion required that the intervention studies randomly assign chil-dren to treatment and control conditions. Randomised controlled trials are considered oneo the best methods to evaluate the relationship between an intervention and outcome
(e.g., Clarke, 1998; Cochrane, 1973).
Criterion 3: Endpoint measures needed to include assessment o language, pre-literacy orliteracy skills. The third criterion required that studies evaluate the efcacy o the inter-vention/practice via assessment o childrens language and literacy skills. Specifcally, aterthe intervention had been presented, children in the Intervention and Control Groupsneeded to be presented with a test assessing their language, pre-literacy or literacy skills.It should be noted that some o the studies identifed in the systematic reviews only mea-sured the eectives o intervention on cognitive and behavioural development. Sincethese domains are beyond the scope o this review, they were excluded.
Criterion 4: Psychometric Properties o the Endpoint measures needed to be published orreported in research article: The ourth criterion was that the test assessing language, pre-
literacy or literacy skills needed to have the psychometric properties o the test published.This criterion eectively meant that only studies were included that had used a publishedstandardised test to evaluate the outcomes o an intervention. The most undamental rea-son or including this criterion was so the tests reliability and validity could be known.
Criterion 5: Study needed to report results that could be extracted or meta-analysis. Thefnal criterion required that published studies report enough detail in the results to allowdata to be extracted and converted to an eect size. In this review all result rom the stud-ies were converted to an eect size measure called Cohens d (Rosenthal, 1994). A descrip-tion o this index is provided now provided.
In this review the eectiveness o interventions and practices are quantifed using a nu-merical index called an eect size. An eect size numerically describes the amount o
variance in a dependent/outcome variable that is explained by the independent/predictorvariable. In the context o examining interventions, an eect size quantifes the magni-tude o dierence between treatment and control groups ollowing treatment/interven-tion. The larger the eect sizes, the larger the dierence between treatment and controlgroups.
The eect size can be considered to operate as a unction o many observed and unob-served variables. In randomised controlled trials, the eectiveness o the intervention/treatment is considered to be a key determinant o the magnitude o the eect size. Anoth-er contributing actor is the measurement error or reliability o the tests used to measureoutcome. As the measurement error o the test increases, the eect size decreases (Hunter& Schmidt, 1990). In the context o this review, measurement error is a concern or at
least two reasons. The frst is that tests that have a high level o measurement error pro-duce small eect sizes. Thus i an intervention is eective and the test used to measurelanguage or literacy outcomes is poorly constructed, this will produce small eect sizes.Perhaps the most troublesome case arises when comparing the results o two or morestudies that examine dierent language or literacy interventions using dierent tests thathave dierent levels o measurement error. I one o the tests has a high level o measure-ment error (i.e., is a bad test) and the other low (i.e., is a good test), even i the eective-ness o the dierent intervention is the same, studies that have bad tests will produceresults suggesting the intervention does not work even though it does. This in turn willlead to incorrect conclusions about the eectiveness o an intervention.
The criterion that studies need to have psychometric properties reported was to be able tocontrol or the aorementioned problems. Published standardised tests not only almost al-
ways have psychometric properties published, but oten these are verifed by independentresearch teams and published in peer review journals. This stands in contrast to studieswhere researchers have devised their own test and do not report thepsychometric properties o their instrument.
A brief overviewof effect sizes and
Cohens d
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Quantiying the Efcacy o Programs/Practices: Eect sizes, statistical signifcance, preci-sion, consistency o eects and clinical importance.
A central outcome o this review is to be able to compare dierent programs/practices. In
order to achieve this goal, it is necessary to quantiy the results o all the dierent studiesso they are on the same scale. The process and rationale by which this is achieved is anal-ogous to converting dierent measures o distance (e.g., eet, inches) into centimetres. Thescale used in this review to evaluate the dierent intervention studies is called Cohensd (Cooper, Hedges, & Valentine, 2009). This index describes the dierence between twogroups in terms o a standardised mean dierence. Cohens d is one type o eect size. Asa guide to interpreting this value, when the Cohens d value is equal to zero, this meansthere is no dierence between two groups. In the context o intervention studies, a valueo zero would mean that there is no evidence to suggest that an intervention/practice isassociated with better language/literacy outcomes. In this review positive Cohens d valuesindicate that the Intervention Group obtained higher scores on a language/literacy testthat a Control Group. Negative Cohens d value indicates that a Control Group obtainedhigher scores.
In the research literature there is a reasonably well-accepted taxonomy interpreting Co-hens d values (Cohen, 1988), whereby a value o 0.2 is considered a small eect size, 0.5is medium and 0.8 is large. Cohens d can also be considered to measure the amount ooverlap between two distributions. For example, when Cohens d = 0 there is 100% overlapin scores between the Control Group and Intervention Group (i.e., there is no dierencebetween groups) and when Cohens d = .8 there is 52.6% overlap in distributions (i.e., thereis a dierence between the groups). In short, in the context o this review, larger positiveeect size values indicate that an intervention/practice is eective.
Another issue that needs to be taken into account when comparing dierent Cohens dvalues between dierent studies is how precise or accurate the value is. Any Cohens dvalue observed or a particular study describes how eective an intervention was or theindividuals participating in that study. However, in this review the ocus is in on beingable to generalise the result rom a specifc study or sample to a broader population. Thus,the question o interest in this review is how well a Cohens d value accurately represents
the type o eect that would be observed i an intervention was administered to all chil-dren. One actor that inuences how well we can generalise the results rom a specifcstudy to a population is the sample size. It is important to rememberthat when a study is undertaken a sample o children/adults is takenrom a population. The larger the sample is, the more accurately thefndings o the study will represent the whole population (assuming
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random selection o participants). Thus, a study which has 1000 participants almost al-ways will be more accurate than a study that has 20 participants. When comparisons aremade between studies, it is important that the precision o the Cohens d value is takeninto account. For example, consider the ollowing scenario. Suppose a study reported a
Cohens d value o .8 but only and 10 people participating and another study reported avalue o .3 but had 3000 people participating. Which study should we put the most conf-dence in? All things being equal, the answer would be the second study with 3000 becauseit has more people and thereore the eect size value is more likely to be accurate.
Statisticians have developed various methods or measuring how precise an observed e-ect size is, given the number o people there are in a study. One approach is to use con-fdence intervals (Gardner & Altman, 1986). Confdence intervals provide us with an esti-mate o how precise an eect size, like Cohens d, might be. When we compute a valueor Cohens d, we can then determine the confdence interval or that value. The conf-dence intervals tell us with a specifed level o probability, what the real (or population)value might be. Confdence intervals comprise two values, a lower and an upper value.For example, suppose a study that reports an eect size o .5. Based on the studys sample
size, we can then work out confdence intervals. The lower value might be .3 and the up-per value might be .7. The population value is thought to be somewhere between .3 and.7. In research, it is common to compute confdence intervals so they tell us that the realvalue is likely to lie between the upper and lower value and we can assert this with a prob-ability o 95%. That is, we expect to be correct 95 times out o 100 (or incorrect 5 times in100). In this review we report confdence intervals or all observed eect sizes.
In some o the analyses in this review, Cohens d values rom dierent studies are com-bined and an overall average is computed. Eect sizes rom dierent studies can be com-bined using fxed- or random-eects models. In this review all eect sizes were combinedusing a random-eects model (or details see Hedges & Vevea, 1998). In random-eectsmodels, the averaged Cohens d value (or any averaged eect size) is considered to repre-sent the central tendency o a population o dierence eect sizes. In principle, adoptinga random-eects model to derive an average eect size computed rom multiple individualstudies allows one to make generalisations beyond the methodology o the individual stud-ies.
Another aspect o the research fnding examined is the amount o variability there is be-tween studies. When comparing Cohens d values rom groups, the eect sizes will vary.Some o this variation is attributable to chance, such as dierences due to the randomselection o participants to be involved in the study. However, another source o variationmight reect more meaningul dierences. In this review the amount o heterogeneitybetween studies is to be quantifed using the I2 statistic. This statistic expresses, as apercentage, the amount o variation or heterogeneity between studies that is not due tochance. A rough taxonomy has been orwarded whereby 25% variation is considered low,
50% moderate and 75% high (Higgins, Thompson, Deeks, & Altman, 2003).
Combining Resultsin DifferentStudies
MeasuringVariabilityBetween Studies
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3 articles included in the
final review7 articles found at CfB
by searching reference
lists.
Number of articles included
in the review
41
1507 articles found
from keyword search in
PubMed og PsycInfo
with limiters at CfB
Articles screened
manually for
relevance
42 studies identified by
Burger (2010), Bus et
al. (1995), Chambers et
al. (2010), Manz et al.
(2010), McGroder &
Hyra (2009), Mol et al.
(2008), National Early
Literacy Panel (2008),
and Reese et al. (2010)
160 articles selected by
title, abstract and/or
keywords.
8 articles removed due
to selection criteria,
although included in
the Danish materials.
3 articles removed here
due to selection criteria,
but included in the
Danish materials.
34 studies
3 studies4 studies
Studies, Curricula/Programs and Measures included in the Review
Ater applying the criteria outlined in Figure 1, a total o 41 studies were identifed thatmet the criteria. A brie description o each study is presented in Table 2.
Figure 1 Process or identiying studies
The 41 fles came rom three main sources: reviews, database searches, and the reerencelists rom the articles we ound. The 11 articles that were disallowed here due to selectioncriteria are included in the Danish material, Forskningskortlgning a behov or sprogvur-dering, eektive sprogindsatser og pdagogisk eteruddannelse.
Studies used in thereview
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Table2.Desc
riptionofStudiesIncludedintheReview
Study
Country
Meanageof
participants
(Months)
Socio-Econom-
icStatusofthe
Sample
Ethnicity
Bilingual
Intervention/Practices
Trialed
Intervention
Group/s
Con
trolGroup
AbtAssociates
Inc.
(2007)
United
States
Notstated.
Onlynoted
thatpartici-
pantswereof
schoolage
Mixed
Mixed
Mixed
BreakthroughtoL
it-
eracy
Breakthroughto
Literacy(n=350)
Providedwithma-
terials
only.Didnot
follow
curriculum(n
=580
AbtAssociates
Inc.
(2007)
United
States
Notstated.
Onlynoted
thatpartici-
pantswereof
schoolage
Mixed
Mixed
Mixed
BuildingEarlyLan-
guageandLiteracy
BuildingEarlyLan-
guageandLiteracy
(n=319)
Providedwithma-
terials
only.Didnot
follow
curriculum(n
=648)
AbtAssociates
Inc.
(2007)
United
States
Notstated.
Onlynoted
thatpartici-
pantswereof
schoolage
Mixed
Mixed
Mixed
ReadySetLeap!
ReadySetLeap!(n
=350)
Providedwithma-
terials
only.Didnot
follow
curriculum(n
=648)
Aram(2006)
Israel
47
LowSES
Mixed
Notstated
1.DialogicReading;
2.AlphabeticSkills
Program;3.Combined
StorybookReading&
AlphabeticSkills
1.StorybookRead-
ingProgram(n=37)
2.AlphabeticSkills
Program(n=38)3.
Combined(n=40)
Untreated/standard
educationalpractice
(n=41)
Aram&Birron
(2004)
Israel
45
LowSES
Mixed
83.3%of
samplespoke
Hebrewas
theirrstlan-
guage;16.7%
spokeRussian
astheirrst
language.
1.DialogicReading;2.
AlphabeticSkillsP
ro-
gram
1.JointReading(n=
38);2JointWriting
(n=38)
Untreated/standard
educationalpractice
(n=24)
Arnoldetal.(1994)
United
States
29
MiddletoUpper
Notstated
Notstated
1.DialogicReadi
ng
1.DirectTraining
(n=23);2Video
Training(n=14).
Childrenreadtoin
normalmanner(n
=27)
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Study
Country
Meanageof
participants
(Months)
Socio-Econom-
icStatusofthe
Sample
Ethnicity
Bilingual
Intervention/Practices
Trialed
Intervention
Group/s
Con
trolGroup
Asseletal.(2007)
United
States
55
Mixed
Mixed
Mixed
DoorstoDiscove
ry
DoorstoDiscovery
Controlclassroom
characterisedbya
lack
ofspeci-
edcu
rriculumthat
include
dascopeand
sequenceofactivi-
ties.
(Asseletal.,
200
7,p.475)
Bakeretal.(19
98,
Cohort1)
United
States
58
LowSES
Mixed
Acrossboth
Cohorts
34.6%ofthe
sampledid
notspeak
Englishas
theirrstlan-
guage.
1.HIPPYProgram
1.HIPPY(n=37)
Standa
rdpractice(n
=32)
Bakeretal.(19
98,
Cohort2)
United
States
54
LowSES
Mixed
1.HIPPYProgram
1.HIPPY(n=47)
Standa
rdpractice(n
=66)
Bierman(2008)
United
States
48
LowSES
Mixed
English&
Spanish
1.REDIProgram
1.REDIProgram&
HeadStart
Head
StartOnly
(stand
ardpractice)
Chow&McBride-
Chang(2003)
HongKong,
China
64
Notstated
Chinese
Cantonese
1.DialogicReadi
ng
1.DialogicReading
(n=27)2.Typical
Reading(n=25)
Nosys
tematicread-
ingor
provisionof
books(n=28)
Chowetal.(20
08)
HongKong,
China
64
Unclear
Chinese
Cantonese
1.DialogicReadi
ng
withMorphologyTrain-
ing(morphologic
al
awareness);2.Dia-
logicReading;3Typical
Reading(n=37
)
1.DialogicReading
withMorphological
Training(n=38);2.
DialogicReading(n
=37).
Nobookswere
provided.Parents
engageinnormal
practicewithchil-
dre
n(n=36)
Crain-Thoreson
&
Dale(1999)
United
States
52
Childrenwith
specialeduca-
tionalneeds,
SESnotexplic-
itly
Notstated
Notstated
1.DialogicReadi
ng
1.ParentDialogic
Reading(n=10);
2.TeacherDialogic
Reading(n=13).
Stand
ardpractice
(whichdidinclude
group
storytime;n
=9)
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Study
Country
Meanageof
participants
(Months)
Socio-Econom-
icStatusofthe
Sample
Ethnicity
Bilingual
Intervention/Practices
Trialed
Intervention
Group/s
Con
trolGroup
Cronanetal.(1
996)
United
States
28
LowSES
MainlyLa-
tino(Note:
Studycon-
ductedinthe
U.S.)
English&
Spanish
1.DialogicReadi
ng
1.Highnumberof
instructionalvisits/
DialogicReading
(n=83);2.Low
numberofinstruc-
tionvisits/Dialogic
Reading(n=73).
Typicalhomerear-
ingpractices(n=
69)
Fischeletal.(2
007)
United
States
Agedbetween
45and60
Mixed
Mixed
Mixed
LetsBegingwith
the
LetterPeople
LetsBeginwiththe
LetterPeople(n=
185)
High
/Scopecur-
riculum
materials(n
=150)
Fischeletal.(2
007)
United
States
Agedbetween
45and60
Mixed
Mixed
Mixed
Waterford
Waterford(n=172)
High
/Scopecur-
riculum
materials(n
=150)
Girolamettoetal.
(1995)
Canada
29
Childrenwith
languagedelays,
SESnotstated
Notstated
English
1.FocusedStimula
tion
1.FocusedStimula-
tion(n=8)
Delay
edtreatment
(n=7)
Huebner(2000)
United
States
29
Mixed,includ-
inginfantsat
riskforlan-
guageproblems.
Mainlywhite
English
1.DialogicReadi
ng
1.DialogicReading
(n=88)
2.Co
ntrolGroup
(provid
edwithsame
resourcesastreat-
mentgroup,but
notprovidedwith
inform
ationabout
dialo
gicstyleof
reading
,i.e.,childas
centre
ofthestory
telling;n=41).
Lonigan&Whitehu-
rst(1998)
United
States
45
LowSES
Notstated
English
1.DialogicReadi
ng
1.SchoolReading;
2.HomeReading;
3.School&Home
Reading
Stand
ardpractice
Loniganetal.(1999)
United
States
45
LowSES
MainlyAf-
ricanAmeri-
cans
Notstated
1.Shared/TypicalR
ead-
ing2.DialogicReading
1.Shared/Typical
Reading(n=29);2.
DialogicReading(n
=34)
Standardpreschool
curriculum(n=32)
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Study
Country
Meanageof
participants
(Months)
Socio-Econom-
icStatusofthe
Sample
Ethnicity
Bilingual
Intervention/Practices
Trialed
Intervention
Group/s
Con
trolGroup
McGill-Franzenetal.
(1999)
United
States
Notclearly
stated(e.g.,
Inthepaperit
isonlynoted
that...some
childrenwere
only4yearso
f
ageatpretest-
ingandother
childrenwere
nearage6.,
p.69)
Mixed:Low
SESandNon-
LowSES
Notstated
Notstated
1.GeneralistLiteracy
Promotion
1.TeacherTraining
&Books(n=164);
2.Books(n=139).
Noboo
ksORteach-
ertrain
ing(n=153)
PCER(2008)
United
States
55
Mixed
Mixed
Notstated
LanguageFocusedCur-
riculum
LanguageFocused
Curriculum(n=97)
High
/Scopecur-
riculum
materials(n
=93)
PCER(2008)
United
States
55
Mixed
Mixed
Notstated
DLMwithOpenCourt
Reading
DLMwithOpen
CourtReading(n=
101)
High
/Scopecur-
riculum
materials(n
=97)
PCER(2008)
United
States
55
Mixed
Mixed
Notstated
LiteracyExpress
LiteracyExpress(n
=90)
High/Scopecur-
riculummaterials(n
=8
6)
PCER(2008)
United
States
54
Mixed
Mixed
Notstated
ReadySetLeap!
ReadySetLeap!(n
=149)
High/Scopecur-
riculummaterials(n
=120)
PCER(2008)
United
States
54
Mixed
Mixed
Notstated
BrightBeginnings
BrightBeginnings
(n=103)
Nonspeciccurri-
culawithafocuson
basicschoolreadi-
ness(n=105)
PCER(2008)
United
States
55
Mixed
Mixed
Notstated
DoorstoDiscove
ry
DoorstoDiscovery
(n=101)
Teacher-developed,
nonspe
ciccurricula
(n=96)
PCER(2008)
United
States
55
Mixed
Mixed
Notstated
LetsBeginwiththe
LetterPeople
LetsBeginwiththe
LetterPeople(n=
100)
Teacher-developed,
nonspe
ciccurricula
(n=73)
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Study
Country
Meanageof
participants
(Months)
Socio-Econom-
icStatusofthe
Sample
Ethnicity
Bilingual
Intervention/Practices
Trialed
Intervention
Group/s
Con
trolGroup
PCER(2008)
United
States
55
Mixed
Mixed
Notstated
ProjectApproach
ProjectApproach(n
=114)
Teacher-developed,
nonspe
ciccurricula
(n=90)
PCER(2008)
United
States
55
Mixed
Mixed
Notstated
CreativeCurriculum
CreativeCurriculum
(n=7
8)
Nonspeciccurri-
culawithafocuson
basicschoolreadi-
ness(n=105)
PCER(2008)
United
States
54
Mixed
Mixed
Notstated
CreativeCurriculum
CreativeCurriculum
(n=97)
Teacher-developed,
nonspeciccurri-
cul
a.(n=97)
Reeseetal.(20
10)
United
States
50
LowSES
Mixed
Acrossthe
different
intervention
andcontrol
groups,per-
centageof
bilingualchil-
drenranged
from41.7-
60%
1.ElaborativeRemi-
niscing2.Dialog
ic
Reading
1.ElaborativeRem-
iniscing(n=12);2.
DialogicReading(n
=10)
Notraining/Standard
Paren
talcare(n=
11)
Robertson&
Wesimer(1999)
United
States
25
Latetalking
infants,Middle
Classhomes
White
English
1.InteractiveChild
CenteredIntervention
1.InteractiveChild
CenteredInterven-
tion(n=11)
DelayedTreatment
(n=10)
Valdez-Mencha
ca&
Whitehurst(1992)
Mexico
31
LowSES
Native
Spanish
1.DialogicReadi
ng
DialogicReading
Arts&
CraftInstruc-
tion
vanBalkometal.
(2010)
TheNether-
lands
25
Developmen-
talLanguage
Delay,Middle
ClassFamilies
Notstated
Notstated
1.VideoHomeTraining
2.DirectChildLan-
guageIntervention
1.VideoHome
Training(n=11)2.
DirectChildLan-
guageIntervention
(DCI;n=11)
Nonon-treatment
con
trolgroup
Wasik&Bond
(2001)
United
States
51
LowSES
African
American
Notstated
1.DialogicReadi
ng
1.DialogicReading
(n=61)
Participatedinarts,
craft
andscience
activities(n=63).
Wasik&Bond
(2006)
United
States
46
LowSES
African
American
Notstated
1.DialogicReadi
ng
1.DialogicReading
(n=139)
Provid
edwithsame
boo
ks(n=68)
-
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13/48
13Forsknings-rev
iew-Sprogpakken.dk
Study
Country
Meanageof
participants
(Months)
Socio-Econom-
icStatusofthe
Sample
Ethnicity
Bilingual
Intervention/Practices
Trialed
Intervention
Group/s
Con
trolGroup
Whitehurstetal.
(1988)
United
States
29
MiddleSES
Notstated
Notstated
1.DialogicReadi
ng
1.DialogicReading
(n=29)
Normalreading
Whitehurstetal.
(1994)
United
States
42
LowSES
Mixed
Mainlyfrom
English
speaking
homes
1.DialogicReadi
ng
1:Teachers&Par-
ents(n=20);2
Teachersonly(n=
26)
Noreading(n=24).
Childreninthecon-
trolconditionen-
gaged
insupervised
playsessions.
Whitehurstetal.
(1999)
United
States
Notstated.
Paperonhly
reportschil-
drenwerein
the2ndGrade
LowSES
Notstated
90%of
samplespoke
Englishas
theirrstlan-
guage
1.CombinedDialo
gic
Reading&SoundF
oun-
dations
1.CombinedDia-
logicReading&
SoundFoundations
RegularHeadStart
Cu
rriculum
Zevenbergenet
al.
(2003)
United
States
56
LowSES
Mixed
Notstated
1.DialogicReading&
HeadStartProgram
(n
=71)
1.DialogicReading
&HeadStartPro-
gram(n=71)
RegularHeadStart
Curriculum(n=52)
-
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14/48
Curricula, Interventions and PracticesEvaluated in Studies that Met Criteria.The studies included in the review, collectively evaluated 22 dierent programs/prac-tices that aim to improve language and literacy skills in young children. These program/practices are summarised in Table 3. There is considerable diversity in the range o pro-grams/practices covered in the studies that met the criteria or inclusion into this review.Some programs/practices can best considered as a complete structured curriculum orimplementation into day care (e.g., Bright Beginnings, see Table 3 or summary). Otherprogram/practices comprise a single task. The dialogic reading program best typifes thisapproach (e.g., Whitehurst, et al., 1988). Another type o program/practices identifed in-volving combining structured curriculum with a single task. For example, Bierman (2008)examined the eectiveness o combining a dialogic reading program with a phonologicalawareness program. Dierences between the program/practices also exist with respect toimplementation. The studies included in this review included program/practices that have
been implemented by teachers, (e.g., Baker, et al., 1998) and speech pathologists (Robert-son & Weismer, 1999).
14
Forsknings-review - Sprogpakken.dk
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15Forsknings-rev
iew-Sprogpakken.dk
Table3.Sum
maryofPrograms/PracticesEvaluatedintheStudiesInclude
dintheReview.
Name
Description
Intervention/Curriculum/Practice
Study/Studiesevaluati
ngInter-
vention/Curriculum/Practice
Break
through
toLiteracy
Break
through
toLiteracy
isasystemat
ican
dintegrated
lit-
eracyan
dlanguageprogrampu
blished
by
the
Wrigh
tGroup,
whichaimsatpromot
ing
language
developmen
tan
dliteracy
skillsamongpresc
hoo
lch
ildren.T
heprogramusessystematic,
direc
tinstruct
ion
bu
iltaroun
daseriesowee
klybooks
inthe
classroom.I
nteract
ivecompu
terprogramsarealsouse
dto
engagestu
den
tsinindividua
lize
dac
tivi
ties,a
ndareorgan
ized
aroun
dthewee
klyboo
k,t
osuppor
ttheir
literacysk
illsan
d
prin
tknow
ledge.
(Cham
bers
etal.,
2010
,p.1
3)
Curr
icu
lum
/Program
AbtAssoc
iates(20
07)
Brigh
tBeg
in-
nings
Brigh
tBeg
inn
ings
isan
integratedcurr
icu
lumw
itha
ocus
onlanguagean
dearly
literacy.
Thecurr
icu
lumgoalsare
to
provi
deach
ild-cen
tere
d,l
iteracy-ocuse
dprogram
that
iscon-
sisten
tan
dtoinclu
de
instruc
tion
thatad
dresses
thenee
dso
thew
holech
ild
.Thecurr
iculumwasespec
ially
des
igned
to
provi
decon
tinu
ity
inthepresc
hoo
ltosecon
d-gra
decurr
icula.
Brigh
tBeg
inn
ings
inclu
desn
inecurr
icu
lumun
its
that
ocus
onlanguagean
dliteracy,m
athemat
ics,socialan
dpersonal
developmen
t,hea
lthulliving,sc
ien
tifc
thinking,socialstud-
ies,crea
tivear
ts,p
hys
ical
dev
elopmen
t,an
dtechnology.
The
classroomenvironmen
tisdesigned
toencouragech
ildren
s
activeexp
lora
tionan
dinteract
ionw
ithadu
lts,ot
herch
ildren,
andconcretemater
ials
.Thec
urr
icu
lumalso
inclu
desaparen
t
invo
lvemen
tcomponen
tthat
requ
iresparen
tstobeac
tive
ly
engage
dinthech
ildseducat
ion
(Cham
bersetal.,
2010
,p
13).a
Curr
icu
lum
/Program
PCER(2008)
Bu
ilding
Early
Languageand
Literacy
(BELL
)Bu
ilding
Ear
lyLanguageand
Literacy
(BELL)isapresc
hoo
l
supp
lemen
taryprogramaimedatpromot
ingpresc
hoo
lers
general
languagepro
fciency,
phonolog
icalawareness,shared
read
ingsk
ills
,an
dprin
tknow
ledge.C
hildrenrece
ive
two
15-
20m
inu
tes
lessons
dai
ly.C
hildren
slitera
ture
isuse
dinclass-
rooms
tobu
ildvoca
bu
laryan
dpromoteawarenessostory
sequencingan
dcharac
ters.T
heprogramalso
inclu
desshared
read
ing
timean
dp
honologicalawareness
time
tosuppor
t
read
ingsk
illsan
dp
honet
icrea
ding
techn
iques.
(Cham
berse
t
al.,
2010
,p.1
6)
Curr
icu
lum
/Program
AbtAssoc
iates(20
07)
-
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16/48
16Forsknings-rev
iew-Sprogpakken.dk
Name
Description
Intervention/Curriculum/Practice
Study/Studiesevaluati
ngInter-
vention/Curriculum/Practice
Creat
ive
Cur-
ricu
lum
Creat
ive
Curr
icu
lum
isacom
pre
hensiveapproac
htoeduca-
tion
or
three-
tofve-year-old
children.T
hecurr
icu
lumad-
dresses
ourareaso
developmen
t-soc
ial/emot
ional,p
hys
ical,
cogn
itive,an
dlanguage
deve
lopmen
t.Creat
ive
Curr
icu
lum
requ
ires
thep
hys
icalspaceo
theclassroom
tobestructured
into10interestareas:
blocks,d
ramat
icp
lay,
toysan
dgames,
art,library,d
iscovery,
san
dan
dwater,
musican
dmovemen
t,
cook
ing,an
dcompu
ters.T
im
eisalsoal
lotted
orou
tdoor
activi
ties.T
he
10interestareasare
des
igned
toad
dresscur-
ricu
lumcon
ten
t,suchas
literacy,m
athemat
ics,sc
ience,s
ocial
stu
dies,
thear
ts,a
ndtechnology,
ina
airlyunstructure
dset-
ting
des
igned
topromotechi
ldren
sprocesssk
ills
,suchasob-
serv
ing,exp
loring,an
dproblemso
lving.
Creat
ive
Curr
icu
lum
inclu
desa
Developmen
talCh
ecklist
teac
hersareas
ked
touse
inongo
ingassessmen
tsoch
ildprogress
(Cham
bersetal.,
2010
,p.1
6).
Curr
icu
lum
/Program
PCER(2008)
DLMw
ith
Open
Court
Rea
ding
The
DLMEar
lyChildhoo
dExpress
Program
isacompre
hen-
sivecurr
icu
lum,d
esigned
topromotech
ildren
ssocial,e
mo-
tional,i
ntellec
tual,
aest
hetic,
andp
hys
ical
developmen
t.Open
Court
Rea
ding
Pre-
Kcon
tains
eigh
tthemat
icun
its
thatad
dress
children
siden
tity
,am
ilies,
rien
ds,social
interact
ions,
trans-
por
tation,t
hep
hys
icalsenses,nature,
andtransi
tions.
(rom
http://www.b
estevi
dence.o
rg/early/early_ch
ild
_ed/top.h
tm)
Curr
icu
lum
/Program
PCER(2008)
-
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17/48
17Forsknings-rev
iew-Sprogpakken.dk
Name
Description
Intervention/Curriculum/Practice
Study/Studiesevaluati
ngInter-
vention/Curriculum/Practice
Doors
toDis-
covery
The
Doors
toDiscoverycurr
icu
lum
isapresc
hoo
lprogram
that
isbasedon
theareas
iden
tifedas
impor
tan
tor
literacy
success:oral
language,p
hono
logica
lawareness,concep
tso
prin
t,alp
habet
know
ledge,w
riting,an
dcompre
hension.T
he
program
ocuseson
theuseo
learn
ingcen
tersan
dshared
literacyac
tivi
ties
inthepresc
hoo
lclassroom.T
hecurr
icu
lum
ispresen
tedineigh
tthematicun
its
thatcover
top
icssuchas
rien
dsh
ip,
commun
ities,nat
ure,s
ociety
,an
dhea
lth
.Class-
roompract
ices
inclu
de
largean
dsmal
lgroup
teac
her-d
irec
ted
activi
tiesan
dch
ildren
sappl
icat
ionosk
illsan
dindepen
dent
pract
iceonac
tivi
ties
thatare
relatedtothe
themes.T
hecur-
ricu
lumcomponen
tsalso
include
am
ily
learn
ingac
tivi
ties
thatare
des
igned
toosterpa
rtnersh
ips
between
thesc
hoo
l
andthe
am
ily;
initialtrainin
gor
teac
hersan
dongo
ingpro-
ess
ional
developmen
tsupport;an
dassessmen
tstra
tegies
that
are
integrated
intothecurricu
lumun
its.
(Cham
bersetal.,
2010
,p.2
1)
Curr
icu
lum
/Program
Asseletal.(
2007);PCE
R(2008)
Language
Focussed
Cur-
ricu
lum
The
Language-
Focuse
dCurri
culum
(LFC)was
developedat
the
Un
iversi
tyo
Kansas
orusew
iththree-
tofve-year-ol
dch
il-
drenw
ithlanguage
lim
itations,
inclu
dingch
ildrenw
ithlan-
guage
impairmen
t,ch
ildren
rom
disadvan
tage
dbac
kgrounds
,
andEngl
ishlanguage
learner
s.Thecurr
icu
lum
hasa
thematic
organ
izat
ionan
docuseson
theuseo
dai
lydramat
icp
lay
to
teac
han
duse
lingu
isticconcep
ts.T
hereare
bot
hteac
her-le
d
andch
ild-le
dac
tivi
tiesw
ithe
xp
lici
tat
ten
tion
toora
llanguage
developmen
tthat
isen
hance
dby
high-qual
ity
teac
her-c
hild
conversat
ions.
Teac
hersusee
ightspec
ifc
languagest
imu
la-
tion
techn
iquesw
hen
interac
tingw
ithch
ildren
intheclass-
room,s
uchaseven
tcasts.
(Cham
bersetal.,
2010
,p.2
5)
Curr
icu
lum
/Program
PCER(2008)
Lets
Beg
in
withthe
Letter
Peop
le
Let
sBeg
inw
iththe
LetterPeop
leemp
has
izesearly
language
andliteracy
developmen
tthr
oughp
lay.
Inad
dition
toclass-
room
teac
hing,
theprogram
hasastrong
home/paren
tcompo
-
nen
t.Thecurr
icu
lum
isarran
gedinthe
ollow
ing
fve
themes:
1)AllAbou
tMe,
2)An
imals,A
nimals,an
dAn
imals,
3)Every-
one
Has
Nee
ds,
4)Get
ting
Alo
ngw
ithOthers,an
d5)NatureA
ll
Aroun
dUs.
(Cham
bersetal.,2
010)
Curr
icu
lum
/Program
PCER(2008)
-
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18/48
18Forsknings-rev
iew-Sprogpakken.dk
Name
Description
Intervention/Curriculum/Practice
Study/Studiesevaluati
ngInter-
vention/Curriculum/Practice
Literacy
Ex-
press
Literacy
Express
isaprescho
olcurr
icu
lum
that
isdes
igned
topromotech
ildren
semergen
tliteracysk
ills
.Thecurr
icu-
lum
isstructure
daroun
dthemat
icun
its
thataresequence
d
inor
derocomp
lex
ity.
Eac
hun
itinclu
desse
lectedch
ildrens
boo
ks
thatad
dress
theme-relevan
tvoca
bu
lary
orsmal
l-an
d
large-groupread
ingac
tivi
ties.I
nad
dition,e
achthemat
icunit
inclu
dessmal
l-groupac
tivitie
s,con
ducted
three
toour
times
awee
k,
whichprovi
de
homogeneoussmal
lgroupsoch
ildren
withpract
ice
inthesk
illsnee
ded
todeveloporal
language,
phonolog
icalsensi
tivi
ty,a
nd
prin
tawareness.
The
large-group
andex
tensionac
tivi
tiesprov
ideoppor
tun
ities
orch
ildren
to
app
lynew
lyacqu
iredsk
illsin
variedcon
tex
ts.
(Cham
berset
al.,
2010
,p.2
7)
Curr
icu
lum
/Program
PCER(2008)
Projec
tAp-
proac
h
Pro
ject
Approac
hisase
to
teac
hingstra
tegies
thatenab
les
teac
hers
togu
idech
ildren
through
in-dep
thinvest
igat
ionso
realwor
ldtop
ics.
Thecurr
icu
lum
isdes
igned
tousech
ildrens
interestsas
thestar
tingpoin
tororgan
izingan
ddevelop
ing
classroom
learn
ingac
tivi
ties.
Threecurr
icu
lumcomponen
ts
addressch
ildren
slearn
ingnee
ds:spon
taneousp
lay,system-
aticinstruct
ion,
andpro
jectw
ork
.Apro
ject
isdefnedasan
in-dep
thstu
dyoarealworld
top
icthat
iswor
thyoch
il-
dren
sat
ten
tionan
de
ort.P
rojectscan
be
incorporated
into
anex
istingclassroom
instruc
tionalprograman
dcanex
tend
oversevera
ldaysorwee
ks.T
hestructura
leatureso
Proj-
ectApproac
hinclu
de
discuss
ion,f
eldwor
k,r
epresen
tation,
invest
igat
ion,
anddisp
lay.
Du
ring
thepre
lim
inaryp
lann
ing
stage,
the
teac
herse
lects
the
top
icostu
d(basedprimar
ilyon
classroom
learn
inggoals,chi
ldren
sinterests,an
dtheavai
l-
abilityo
loca
lresources
).The
teac
her
then
bra
instorms
his
orherownexper
ience,k
now
ledge,a
ndideasan
drepresents
them
ina
top
icweb.T
histop
icweb
isrevise
dthroughou
tthe
pro
jectan
duse
dorrecordingprogress.
InProjec
tApproac
h
classrooms,
the
dai
lysc
hedule
isstructure
dso
thatch
ildren
andteac
hersspen
dat
leas
t45to60m
inu
tesengage
dininves
-
tiga
tionan
ddiscovery,t
ypica
lly
insmal
lgroups.
(Cham
bers
etal.,
2010
,p.2
9)
Curr
icu
lum
/Program
PCER(2008)
-
7/28/2019 Forskning s Review
19/48
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21Forsknings-rev
iew-Sprogpakken.dk
Name
Description
Intervention/Curriculum/Practice
Study/Studiesevaluati
ngInter-
vention/Curriculum/Practice
Dialogic
Read
-
ingw
ithMor-
phology
Train
-
ing
Inthisprogrammorp
hology
train
ingwasad
ded
todialogic
read
ingpract
ices.T
hemorph
ology
train
ing
invo
lved
ocusing
children
sat
ten
tion
tomorph
osyl
labicproper
tieso
language
andtoiden
tiymorp
hemes.
Childrenwerealsoprovi
dedwit
h
homop
hone
train
ing
that
ocuse
don
train
ingch
ildren
that
thesamesoun
dm
ighthaved
ieren
tmean
ings.
Chowetal.(
200
8)
Focuse
dStim-
ulation
The
Focuse
dStimu
lationprogramwas
rom
the
Hanen
Pro-
gram
that
trainsparen
tsto:
(a)ol
low
thech
ildslead
toes-
tablisha
jointocus,
(b)mode
llanguage
that
iscon
tingen
ton
thech
ildsocus
(e.g.,
labels,expansions,commen
ts)an
d(c)
encourage
thech
ildspar
ticip
ation
inconversat
ion
bypromo
t-
ing
turn-tak
ing.
Thisprogram
con
ten
twasadap
tedtoinclude
threemod
ifca
tionsconsisten
tw
itha
ocuse
dst
imu
lation
approac
h.F
irst,m
otherswere
taugh
ttointroducespec
ifc
targetwor
ds
during
thesecon
dparen
ttrain
ingsess
ion.T
en
othe
20se
lectedwor
dswereran
dom
lyassigned
tothe
targe
t
wor
dcon
dition
by
the
invest
igators.
Paren
tsweregivena
list
othe
targetwor
dsan
dinstructed
touse
them
innatura
listic
rou
tines.F
orexamp
le,
iatargetwor
dwas
baby,t
heparen
t
was
instructed
tomodel
thiswor
dinthe
ollow
ingmanner
ina
jointac
tionrou
tineorga
me:
baby.
lets
hug
the
baby,
hug
baby,
you
hug
the
bab
y.
baby,
etc.
Atno
timewas
thech
ildas
ked
torepea
tthe
wor
d.I
nthe
thirdeven
ingses-
sion,
paren
tswere
trained
to
model
thewor
ds
inmany
dier-
entcon
texts,using
dierentexemp
lars
toexpress
dieren
t
inten
tions
(e.g.,
reques
t,commen
t).T
heparen
tsuseo
target
wor
dswasreviewed
duringeac
heven
ingsess
ion,a
ndparents
kep
tdiarieso
thech
ildsimitat
ivean
dspon
taneouspro
duc-
tiono
thesean
dot
herwords.
Secon
d,i
nthesix
theven
ing
sess
ion,p
aren
tswere
trained
how
tose
lectad
ditional
lexical
targets.
Third
,in
the
fnaleven
ingsess
ionparen
tswere
taugh
t
toexpan
dtargetwor
ds
intot
wo-wor
dp
hrasesan
dmodel
wor
dcom
binat
ions.
(Girolam
ettoretal.,
1995
,p.4
3).
Girolamet
toetal.(
1995)
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22Forsknings-rev
iew-Sprogpakken.dk
Name
Description
Intervention/Curriculum/Practice
Study/Studiesevaluati
ngInter-
vention/Curriculum/Practice
Literacy
Pro-
mot
ion
Literacy
Promot
ion
invo
lvest
raining
teac
her
insevera
lareas
thatare
though
ttopromoteread
ingamongs
tch
ildren.
This
inclu
desp
hys
ical
des
igno
th
eclassroom;e
ec
tive
boo
kdis
plays;impor
tanceoread
ing
alou
dtoch
ildren;
interact
ive
techn
iques
orread
ingaloud;environmen
talprin
t;au
thor,
genre,
andcon
ten
tthemescr
eatedw
iththe
boo
kco
llec
tion;
smal
l-group
lessonsusing
tea
cher-mademater
ialbasedon
boo
ksread;emergen
twri
ting
ormatch-to-prin
toppor
tun
ities
;
andliteracyac
tivi
tyduringp
lay.
McG
ill-Franzenetal.
(1999)
Elaborat
ive
Rem
iniscing
The
Elaborat
ive
Rem
iniscing
pract
ice
isase
togu
idel
ines
or
verbal
lyinteract
ingw
ithchil
dren
thatare
basedon
thesame
techn
iquesemp
loye
dinthe
dialogicread
ing
interven
tion.
Thisinclu
des
theuseoopen
-en
dedques
tions,
ollow
ing
the
childslead,e
xpan
dingon
thech
ildsu
tterances,an
dlin
king
thepas
teven
ttoot
heraspec
tso
thech
ildsexper
ience.T
hese
pract
icesareaimed
tobeuse
deveryday.
Spec
ifc
Prac
tice
Reeseetal.(
2010)
Interact
ive
ChildCen-
tere
dInterven-
tion
Languagest
imu
lationprovidedspeechpat
holog
ist.Stimu
la-
tion
ocuse
donvoca
bu
larysizean
dtwo-
threewor
du
tter-
ances.
Interven
tion
Rober
tson
&Weismer
(1999)
Dialogic
Rea
dingw
ith
Soun
dFounda-
tions
The
dialogicread
ingcomponen
twassim
ilar
tothat
descr
ibed
earl
ier
inthistable
.The
Soun
dFoun
dat
ionsprogram
isapho
-
nem
icawarenesscurr
icu
lum.
Composi
te
Whitehurs
tetal.(1
999)
0
-
7/28/2019 Forskning s Review
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Synthesis of Research: Meta-analyses &DiscussionCan a curriculum-based approach to early childcare produce results better than teachingadhering to a non-specifc program? The aim o the frst set o comparisons is to addresswhether curriculum/systematic approaches to early education are associated with betterlanguage and literacy skills compared to non-systematic approaches. The results o thesestudies are summarised in Tables 4 - 9. In all o these studies, the intervention comprisesa systematic curriculum or teaching language and pre-literacy skills. The control groupcomprised o non-specifc practices devised by individual teachers. It is important to notethat these studies are evaluating a range o dierent curriculum/programs. These com-parisons do not necessarily inorm which specifc practices are best or supporting earlylanguage and literacy skills in young children. However, by treating all dierent curricu-lum/programs as being representative o a systematic approach to improving language andliteracy in young children the question we can examine is whether, overall, systematic/cur-
riculum based approach is better, the same or worse than non-systematic/non-curriculumbased approach.
Receptive Vocabulary. The frst set o results examined related to receptive vocabulary.Table 4 shows the individual eect sizes and 95% confdence interval or individual stud-ies. At the study level, while all but one study avoured a curriculum approach, the eectsizes were not signifcantly dierent rom zero. However, the average eect size com-puted using all studies was ound to be .120 (a small eect size) which was statistically sig-nifcant rom zero (p = .036). This result indicates that regardless o the intervention used,overall, a curriculum based approach will is associated with a signifcant, albeit, small in-
crease in receptive vocabulary scores.
Question 1
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24Forsknings-rev
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Table4.
IndividualandWeightedAveraged
EffectSizes(Cohensd)ComparingCurriculumandNon-Cur
ricu-
lumApproac
hesonImprovingReceptiveVocabularya.
Study
CurriculumEvaluated
Effect
Sizeb
StandardError
95%CondenceIntervalsfor
theEffectSize
p-value
LowerLimit
UpperLimit
PCER(2008)
BrightBeginnings
0.13
0.14
-0.14
0.40
.353
PCER(2008)
CreativeCurriculum
0.23
0.14
-0.04
0.50
.100
PCER(2008)
CreativeCurriculum
0.08
0.14
-0.19
0.35
.568
PCER(2008)
DoortoDiscovery
0.15
0.14
-0.12
0.42
.284
PCER(2008)
LetsBeginwiththeLetterPeople
-0.04
0.06
-0.16
0.08
.830
PCER(2008)
ProjectApproach
0.16
0.14
-0.11
0.43
.253
WeightedAverage
0.12
0.06
0.00
0.24
.036*
Notes:aAllstud
iesmeasuredreceptivevocabularyusingthePPVT(seeAppendixBfordescriptionofthetest;bPositivevalues
favour
curriculum,neg
ativevaluesfavournon-curriculuma
pproach;*p