Speciﬁc Language Difﬁculties and School Achievement in Children Born at 25 weeks of gestation or less

7/27/2019 Specific Language Difficulties and School Achievement in Children Born at 25 weeks of gestation or less

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Specific Language Difficulties and School Achievement in Children Bornat 25 Weeks of Gestation or Less

DIETERWOLKE, PHD, MUTHANNA SAMARA, MSC, MELANIE BRACEWELL, MD, AND NEIL MARLOW, MD,FOR THE EPICURE STUDY GROUP*

Objective To determine whether language and educational problems are specific or due to general cognitive deficits in

children born at 25 weeks gestation or less.

Study design A national cohort study assessed 241 of 308 (78%) surviving children at a median age of 6 years, 4 months

along with 160 of these childrens classmates. Formal tests included standard cognitive, language, phonetic, and speech

assessments. The childrens school achievement was rated by classroom teachers.

Results Mean cognitive scores for index children were 82 (standard deviation [SD] 19) compared with 106 (SD 12) forthe peer group. Extremely preterm children had an increased risk of language problems (odds ratio [OR] 10; 95% confidence

interval [CI] 3 to 32), speech problems (OR 4.4; 95% CI 3 to 7), and overall school difficulties (OR 25; 95% CI 12 to 54). Extremely preterm boys were twice as likely to show deficits as extremely preterm girls, but no such sex-based

differences were apparent in the comparison group. Differences in general cognitive scores explained specific language or

phonetic awareness deficits, but not speech ratings or educational difficulties, in the extremely preterm children.

Conclusions Language or phonetic difficulties are not specific and indicate general cognitive functional difficulties. The

findings have implications for models of global deviation of brain development in extremely preterm children.

(J Pediatr 2008;152:256-62)

Ahigher prevalence of cognitive impairments and poorer educational achievement has been repeatedly observed inchildren born preterm or with low birth weight compared with children born at full term.1 Other developmentaldisorders, such as language delays and deficits,2 articulation problems,3 and learning disorders (eg, poor reading, writing,

and numerical and mathematic skills4,5) also are more common in very low birth weight (VLBW) children. Such language orlearning disorders may be associated withgeneral cognitive impairment, or they can be specific and independent of cognitivefunction or environmental disadvantage.2 Specific developmental language impairments or specific learning disorders arediagnosed when there is a clear discrepancy between general intellectual development as measured by, for example, performanceIQ and language or learning achievement scores.6,7

Long-term adverse cognitive, language, and psychosocial outcomes have beenreported in children with normal IQ but with specific language impairment. 8 Specificdeficits may suggest either damage to or inhibition of normal development in specific areasof the brain.9 Few previous studies have evaluated whether these developmental orlearning problems truly represent specific developmental disorders or can be accounted forby general cognitive deficits in VLBW children.10

A recent longitudinal analysis of VLBW children suggests that learning difficultiesare not specific, but rather are more likely due to global deficits in cognitive function and

may require different interventions than those developed for full-term children.4 How-ever, the children included in these cohorts were born before the widespread introductionof antenatal corticosteroid and surfactant replacement therapy, which are importantdeterminants of the increased survival of extremely preterm infants11 that can be expectedto enhance long-term outcome and also possibly alter patterns of disability. These cohorts

CI Confidence intervalK-ABC Kaufman Assessment Battery for ChildrenMPC Mental Processing CompositeOR Odds ratio

PAT Phonological Abilities TestPLS-3 Preschool Language Scale-3SD Standard deviationVLBW Very low birth weight

From the Department of Psychology and

Warwick Medical School, Health Sciences

Research Institute, University of Warwick,

Coventry, UK (D.W., M.S.) and the Insti-

tute of Neuroscience, Univers ity of Not-

tingham, Nottingham, UK (M.B., N.M.).Submitted for publication Mar 30, 2007;

last revision received Jun 18, 2007; ac-

cepted Jun 28, 2007.

Reprint requests:DieterWolke, PhD,Univer-

sity of Warwick, Department of Psychology

and Health Sciences Research Institute, War-

wick Medical School, Coventry CV4 7AL, UK.

E-mail:[email protected].

*A list of EPICURE Study Group members

is available at www.jpeds.com.

0022-3476/$ - see front matter

Copyright 2008 Mosby Inc. All rights

reserved.

10.1016/j.jpeds.2007.06.043

256
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included very few extremely preterm children, whose survivalhas increased over the past 15 years and whose high risks ofdisability and general cognitive problems have been describedpreviously.12

In this report, we describe the results of language, speech,phonetic, and educational difficulties during the early school ageperiod in a geographically based sample of children born before26 weeks gestation, of whom 60% were exposed to antenatalsteroid treatment and 84% received surfactant.13We investigatethe extent to which the language and learning difficulties ob-served in this population are specific impairments or are in line

with general cognitive abilities.

METHODS

Subjects

The derivation and characteristics of this study populationhave been described previously,13,14 as have the details of the6-year evaluation.12The population represents all surviving chil-dren born at 25 weeks, 6 days gestational age or less betweenMarch and December 1995. Of the 308 children known to bealive at age 30 months, the parents of 241 consented to the study.

A total of 204 children were in mainstream education. For eachchild assessed in a mainstream school, we sought an age- andsex-matched classmate as a comparison.12Thus, we were able toassess 160 full-term born children, who form the comparisonpopulation. All children were assessed by a pediatrician and apsychologist trained in the techniques used for the study (see

Appendix; available at www.jpeds.com). All appointmentswere made by the study administrator, and the assessors wereblinded to the childrens group status. All parents gave writteninformed consent, and the study was approved by the TrentMulticentre Research Ethics Committee and the local edu-

cation authorities in Scotland.

Assessment

General cognitive ability was assessed using the Kauf-man Assessment Battery for Children (K-ABC),12,15 com-posed of 2 summative scales: the Mental Processing Com-posite (MPC), comprising Sequential and SimultaneousProcessing subscales, which provides a global measure of thechilds cognitive ability, and the Achievement Scale, an as-sessment of knowledge of facts, language concepts, andschool-related skills. Receptive and expressive language abil-

ities were evaluated using the Preschool Language Scale-3(UK) (PLS-3), which comprises Auditory Comprehensionand Expressive Communication scales.16 Articulation diffi-culties were assessed according to 19 speech sounds in theinitial or final positions of consonant-vowel-consonant words,

which the child is asked to imitate in the PLS assessment. Weused the Phonological Abilities Test (PAT)17 to assess skillspredictive of reading acquisition.18 The PAT comprises 4subtests: rhyme detection, phoneme deletion (both beginningand end sounds), and a test of letter knowledge.17 Quality ofspeech was rated by the psychologists using publishedscales;19 phonological disorder (315.39) and stuttering (307)

were diagnosed according to criteria specified in the Diagnos-tic and Statistical Manual of Mental Disorders, 4th edition(DSM-IV).7

Cognitive impairment or disability precluded the use ofthe K-ABC in 41 index children.12 These children wereevaluated using either the Griffiths Scales of Mental Devel-opment20 (in 35 children) or the NEPSY Neuropsychology

Assessment21 (in 6 children). The Griffiths quotient or meanNEPSY standardized score was used to estimate a score. Ifthis score was40 (the lowest score on the K-ABC), then thechild was assigned a score of 39. To give a measure ofcognitive function for all of the index children, these values

were merged with the MPC to give an overall cognitive score.No other substitutions for untestable children were made forthe K-ABC subscales or in reporting other test results.

Teachers rated the scholastic performance of the indexand comparison children against the national expected level ofattainment for a child of the same age in English, mathemat-ics, science, technology, geography, history, and informationtechnology. These ratings were combined to yield a totalacademic achievement score.22

Eight experienced developmental psychologists wererecruited to perform the assessments described above. Allattended a course in which they were trained in all aspects ofthe study evaluation. After the training course, every secondchilds session was videotaped and for random quality checkby the senior assessment psychologist.

Statistical Analysis

Categorical outcomes were compared using the 2 testfor trends, as appropriate, or Fishers exact test. Continuousoutcomes were compared using an independent Student ttest.

All statistical tests were 2-sided. Differences in results be-tween the extremely preterm and comparison children andbetween boys and girls (and their interactions) were evaluatedusing a generalized linear model if scales were normally dis-tributed. A priori dichotomized outcomes were determinedusing a cutoff of 2 standard deviations (SDs) or the 10th/90thpercentiles as appropriate. The comparison scores served ascomparison norms for all tests. Testing for the presence ofspecific learning disabilities was done using multiple regres-sion, with the overall cognitive score (MPC) as a covariate.

All analyses were then repeated after excluding children withsevere physical disability (eg, blindness, hearing loss requiringaids, cerebral palsy).

RESULTS

Cognitive Scores

The mean scores for all children and boys and girlsseparately have been reported in detail previously.12The meanMPC score was 105.7 (SD 1.8) for the comparison chil-dren and 82.1 (SD 19.2) for the extremely preterm chil-dren, a difference of 23.6 points (95% confidence interval[CI] 20.3 to 26.8). In the comparison group, boys and girlshad similar scores. In contrast, index boys (mean, 77.1

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19.6) scored lower than index girls (mean, 87.2 17.4); thedifference in means was 10.1 points (95% CI 5.4 to 14.8),and the sex by group interaction was significant (P .01).

These effects remained after exclusion of children with severephysical disability (mean scores: 81.9 15.2) and 90.6 13.5, respectively; difference of means, 8.7 points; 95% CI 5.1 to 12.3; sex by group interaction, P .01) or when onlythe children tested using the K-ABC were considered (4.6points; 95% CI 1.1 to 8.1).

Compared with the control children (contemporarynorms, 1.3%; n 2), 98 (40.6%) extremely preterm childrenhad a general cognitive ability score (MPC) 2 SD, indi-cating moderate to severe cognitive impairment (P .001).12

Compared with extremely preterm girls (32%; n 38), ex-tremely preterm boys (49%; n 60) were twice as likely tohave serious impairment in overall cognitive scores (OR2.1; 95% CI 1.2 to 3.5; P .01).

Language Abilities

Findings similar to those presented above were observed

when language tests were considered. The extremely pretermchildren exhibited poorer performance in all of the PLS-3composite scores and total score than the comparison children(Table I). The extremely preterm children were more likely tohave serious language impairment, as evaluated by the totalPLS-3 score and auditory comprehension, expressive commu-nication, and articulation subtests (Table I); boys had higherrates of impairment than girls (total PLS, P .01; auditorycomprehension, P .01; expressive communication, P .05;articulation, P .01). No sex differences were found in thecomparison group. Although the interaction between groupand sex was not significant in the PLS-3 using continuous

scores, extremely premature boys were more likely to havemoderately or severely impaired scores than extremely prema-ture girls (total PLS-3: OR 2.3, 95% CI 1 to 5.1, P.05; auditory comprehension: OR 2.1, 95% CI 0.8 to5.5, P .107; expressive communication: OR 5.1, 95%CI 1.8 to 14.3, P .01; articulation: OR 3.2, 95%CI 1.1 to 9.3, P .05).

Using the comparison group as a reference popula-tion, children who scored below the 10th percentile in thePAT or above the 90th percentile for the speech andlanguage ratings were considered to be in the clinical, orabnormal, range. The extremely preterm children weremore likely to have difficulties on all subscales of the PATand were more often rated in the clinical range in speechproduction and grammatical correctness in language by theassessors (Table II). Significant sex differences in the pho-neme deletion beginning sounds (P .01) and in gram-matical correctness ratings (P .01) were found, with anexcess of boys in the clinical range.

Compared with their peer group, the extremely pre-term children were rated as using less developmentallyappropriate speech sounds for age and dialect (17.6% vs6.3%; OR 3.2; 95% CI 1.5 to 6.6; P .01) and hadmore difficulties in speech sound production, defined asinterfering with academic achievement or with social com-munication (14.6% vs 3.1%; OR 5.3; 95% CI 2 to13.9; P .001). These factors compose the DSM-IVclassification phonological disorder (315.39).7 Similarly,the extremely preterm children had more disturbances inthe normal fluency and time patterning of speech(DSM-IV stuttering [307] (5% vs 0.6%; OR 8.3; 95%CI 1.1 to 66.7; P .05).

Table I. Language abilities in the PLS-3 assessed at 6 years for 241 children born at 25 weeks of gestation

or less and 160 age matched classmates for comparison

Comparison group Extremely preterm group

OR (95% CI) for

serious impairmentn Mean (SD)

Serious

impairment

(


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Academic Achievement

The Total Academic Achievement Score classifies chil-dren scoring below average in contrast to average or aboveaverage performance.22A score was assigned to 169 extremelypreterm children and 150 comparison children by mainstreamclass teachers. Missing data are due to teachers not returningcomplete ratings. Of the extremely preterm children in main-stream schools, 50.3% were rated below average, compared

with 5.3% of their peers (OR 17.9; 95% CI 8.3 to 38.9;P .001). The actual risk would have been higher hadchildren enrolled in special schools (who perform well below

what would be expected for age) been included (OR 25;95% CI 12 to 54). Extremely preterm boys in mainstreamschools were more likely to have below-average ratings than

extremely preterm girls in mainstream schools (OR 2.4;95% CI 1.3 to 4.4; P .01).

Specific Language or General Academic Impairment

We explored the possibility of specific language impair-ment using multiple regression to adjust PLS-3 scores, clin-ical ratings for PAT/language scales, and teacher assessmentsfor the general cognitive score (MPC). Cognitive impairmentexplained the differences between extremely preterm childrenand comparison children in PLS-3 total score and the 3subscale scores independent of whether all children (Table

III) or only those without severe disability (not shown) wereanalyzed. For example, although the observed mean differ-

ence in the comparison childrens unadjusted PLS-3 totalscore was 14.3 points (95% CI 10.6 to 18.0), after adjust-ment, this fell to 1.8 points (95% CI 6.6 to 3). Categor-ical comparisons produced similar results. Cognitive impair-ment also accounted for the differences in impairment inphonetic awareness and language ratings (Table IV), but notfor the differences in speech ratings and academic achieve-ment (P .01 and .001 after adjustment, respectively).Speech impairments were still 2.6 times more frequent in theextremely preterm children (95% CI 1.5 to 4.6) afteradjustment for general cognitive ability. Similarly, educationalproblems could not be attributed solely to general cognitive

deficits but remained 4.9 times more frequent (95% CI 2 to11.5) after general cognitive score adjustment (Table IV).

DISCUSSION

In this entire population cohort of extremely pretermchildren in the UK and Ireland, we found considerable dif-ferences in general cognitive ability (IQ), language, phoneticawareness, articulation, and scholastic achievement compared

with their classmates of the same age. These differences weremore pronounced in this population than those observed inother studies of more mature very preterm or VLBW popu-

Table II. Scores in the clinical range or language abilities on the PAT and speech and language ratings

assessed at 6 years for 241 children born at 25 weeks of gestation or less and 160 age-matched classmates

for comparison

Comparison group Extremely preterm group

OR (95% CI)

Number/number

with information Percent

Number/number

with information Percent

PAT

Rhyme detection 22/160 13.8* 66/203 32.5* 3.1 (1.8 to 5.2)*Boys 11/71 15.5 37/96 38.5

Girls 11/89 12.4 29/107 27.1

Phoneme deletion beginning sounds 33/160 20.6* 104/203 51.2* 4.1 (2.5 to 6.5)*

Boys 16/71 22.5* 57/96 59.4*

Girls 17/89 19.1* 47/107 43.9*

Phoneme deletion end sounds 45/160 28.1* 115/203 56.7* 3.3 (2.1 to 5.2)*

Boys 25/71 35.2 57/96 59.4

Girls 20/89 22.5* 58/107 54.2*

Letter knowledge 32/160 20* 76/202 37.6* 2.4 (1.5 to 3.9)*

Boys 19/71 26.8 36/96 37.5

Girls 13/89 14.6* 40/106 37.7*

Speech rating 32/158 20.3* 106/200 53* 4.4 (2.8 to 7.1)*

Boys 14/71 19.7* 48/92 52.2*

Girls 18/87 20.7* 58/108 53.7*

Grammatical correctness rating 23/158 14.6* 66/200 33* 2.9 (1.7 to 4.9)*

Boys 10/71 14.1* 37/92 40.2*

Girls 13/87 14.9 29/108 26.9

Values shown are the proportions scoring over the 90th percentile for the comparison group (PAT) or under the 10th percentile for the comparison group (speech and grammar ratings).ORs are calculated by logistic regression with sex as a covariate.*P .001.P .01.P .05 for differences between extremely preterm and comparison groups.



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lations, in whom disadvantages have been described over awide range of cognitive functions, including informationprocessing, language, phonetic awareness, and educationalachievement.1,19,23,24

In school and everyday settings, children are comparednot with children born in the 1970s, but rather with theirclassmates. Therefore, for all statistical comparisons, includ-ing the classification of impairment, as a reference we used thescores of the comparison group rather than the often outdatedhistorical test norms, which are subject to significant seculartrends in adults and children25 and result in underestimation

of impairment.12,26 Using this comparison, we found that40.6% of extremely preterm children had general cognitivedeficits, and that these children were 56 times more likely tosuffer moderate to severe cognitive deficits compared withmainstream classmates born at full term.

This finding of substantial general cognitive deficits andlanguage, phonetic, and speech impairments cannot be attrib-uted to selective dropout of high achievers. Previously re-ported analysis indicated no differences regarding medical

variables, growth, or early disability between those lost to

follow-up and those assessed.12

Rather, dropout was morelikely in disadvantaged families, which would be expected toreduce cognitive and language achievement,19,27 and thus wemay have underestimated the language deficit in our popula-tion.

When controlling for general cognitive performance, nospecific language difficulties or phonetic deficits were ob-served, a finding reported in previous studies of more matureVLBW and extremely preterm children.19,24 Thus, there islittle evidence that language or phonetic processing problemsin extremely preterm children are due to specific deficitspreviously speculated to be a result of damage to or inhibition

of normal development in specific areas of the brain.

9

Rather,these and previous analyses in 2 other samples19,24 suggestthat language abilities are substantially explained by generalcognitive deficits in extremely or very preterm children. Thisfinding may have its equivalence in brain development, in thatgeneral cognitive impairments in extremely preterm childrenmay have their origin in global changes in brain developmentin terms of size and complexity28-30 and generally are not theresult of damage to specific brain regions. These findings addto our understanding of the neuropathologic pathways asso-ciated with later language function in extremely preterm chil-dren.

Table III. Mean performance and frequency of serious impairment in the EPICure cohort and comparison

group for language abilities on the PLS-3 before and after adjustment for general cognitive scores (MPC)

PLS-3

Unadjusted mean

(95% CI)

Adjusted mean

(95% CI)

Unadjusted OR for

serious impairment

(95% CI)

Adjusted OR for

serious impairment

(95% CI)

Total score

Extremely preterm 89.6 (86.8 to 92.4) 96.7 (94.3 to 99.2) 9.6 (2.9 to 32.2)* 1.3 (0.3 to 5.3)

Comparison 103.9 (101.6 to 106.2)* 98.5 (95.4 to 101.5)

Auditory comprehension

Extremely preterm 88.7 (86.4 to 91.1) 94.1 (91.9 to 96.3) 8.3 (1.9 to 35.7) 1.6 (0.3 to 9.8)

Comparison 101.3 (99.1 to 103.5)* 96.5 (93.7 to 99.3)

Expressive communication

Extremely preterm 92.6 (89.6 to 95.5) 100 (97.4 to 102.6) 10.7 (2.5 to 45.5)* 1.2 (0.2 to 6.5)

Comparison 105.4 (103.1 to 107.8)* 100.5 (97.2 to 103.8)

Articulation screener

Extremely preterm 32.7 (31.7 to 33.8) 34.3 (33.3 to 35.3) 3.9 (1.2 to 11.6) 1.1 (0.3 to 4)

Comparison 34.9 (34.2 to 35.6) 34.5 (33.2 to 35.8)

*P .001.P .05 for differences between the extremely preterm and comparison groups.P .01.

Table IV. ORs for clinical scores in language

abilities and below-average academic performance

on the Total Academic Achievement Score for the

EPICure cohort, before and after adjustment for

general cognitive scores (MPC)

Unadjusted OR for

clinical score

(95% CI)

Adjusted OR for

clinical score

(95% CI)

PAT rhyme detection 3 (1.8 to 5.2)* 1.6 (0.8 to 3.2)

PAT phoneme

deletion beginning

sound

4 (2.5 to 6.5)* 1.2 (0.7 to 2.1)

PAT phoneme

deletion end sound

3.3 (2.1 to 5.2)* 1.1 (0.7 to 2)

PAT letter knowledge 2.4 (1.5 to 3.9)* 1.3 (0.7 to 2.4)

Speech ratings 4.3 (2.7 to 6.8)* 2.6 (1.5 to 4.6)

Language ratings 2.9 (1.7 to 5)* 1.2 (0.6 to 2.3)

Teachers academic

achievement scale

24.9 (11.6 to 53.6)* 4.9 (2 to 11.5)

*P .001.P .01 for differences between the extremely preterm and comparison groups.

260 Wolke et al The Journal of Pediatrics February 2008


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In contrast, speech problems and a global rating ofeducational difficulties could not be explained solely by lowerIQ, a finding replicating the results reported for VLBWchildren in Germany.19 Speech difficulties often involve oralmotor problems31 and may be significantly affected by spe-cific motor problems and controlled by specific brain areas.Oral motor problems, such as in eating difficulties, have longbeen suspected to be associated with later speech problems32

and warrant further exploration. Furthermore, our findingsregarding educational problems are consistent with those re-ported by Taylor et al,24 who found specific mathematicalachievement deficits in children with birth weight 750 g.

Wolke and Meyer19 found that numerical abilities were notsolely accounted for by IQ in a German VLBW sample. Arecent longitudinal study comparing extremely and very pre-term children and full-term control children showed thatgeneral cognitive impairment had a strong initial impact onspecific abilities (phonetic accuracy, letter and number knowl-edge) that are prerequisites for learning reading, writing, andmathematical skills. However, attained reading, writing, and

mathematical abilities are the mediating link to longer-termeducational success in both full-term and preterm children.4

Furthermore, other factors, such as working memory,33 at-tention deficit and peer relationship problems,1,34 motorproblems,35 and family socioeconomic factors,4,24 also con-tribute to educational problems in extremely premature chil-dren and need to be further explored in longitudinal analysis.

This is relevant, because motor or behavioral managementprograms may be able to increase educational performance inextremely preterm children.

A range of adverse perinatal outcomes has been describedin males, ranging from death,36 perinatal brain injury,37 cerebralpalsy, and delayed lung maturation38 to preterm birth andstillbirth. Significant sex differences in cognitive functioninghave been reported in some cohorts38 but not in others.19Wefound a substantial and clinically relevant increase in cogni-tive, language, and educational difficulties in extremely pre-term boys compared with extremely preterm girls. This is inthe context of the lower survival and greater frequency ofneonatal problems13 and higher rates of disability14 in malesin this population. It may be speculated that sex differences inintrauterine development may make the male fetus/extremelypreterm infant particularly vulnerable to perinatal adversityand may have important consequences for later develop-ment.39The gestational age at which male vulnerability is nolonger demonstrable remains to be determined, but it wouldseem to be particularly evident at very low gestational age.

The present study has some limitations. We requiredthe cooperation of the childrens teachers to obtain parentalconsent to communicate the contact details of the controlchildren to the investigators. Lack of teacher cooperation orof parental consent was the major reason why we did not havea class control for all target children. We found no pattern orlack of cooperation according to regional variation or socialdeprivation in the area that the school was serving; thus, weconsider any bias to be minimal. All assessors were unaware of

the childrens group status and family background; however,total blinding throughout the assessment may not have beenachieved in all cases, considering that the extremely pretermchildren were on average smaller, more often required correc-tion for sight, and more often had a motor disability. Thismay have provided clues to the assessors regarding groupmembership.

In conclusion, our findings demonstrate that adversecognitive, language, phonetic, and educational sequelae aremore frequent in extremely premature children than in moremature preterm populations and that the cognitive impair-ment is general rather than specific. Cognitive impairmentsexplain only part of the educational difficulties experienced bythese children, and future analysis needs to take into accountother areas of function, including behavioral, motor, andsocial difficulties. Our findings of patterns of functional dif-ficulties may have important implications for brain imagingresearch.40 Extremely preterm birth and very early extrauter-ine development may alter the pattern of brain developmentacross a range of brain regions, including all areas of the cortexand deeper brain structures,28 and may be responsible for theglobal deficits in neuropsychological function seen in this

vulnerable population.

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APPENDIX

The EPICure Investigator Group: K Costeloe(London), AT Gibson (Sheffield), EM Hennessy (Lon-don), N Marlow (Nottingham), AR Wilkinson (Oxford),D Wolke (Warwick). Developmental Panel: Psycholo-gists: Emma Luck, Catherine Bamford, Helen Betteridge,Hanne Bruhn, Sandra Johnson, Iliana Magiati, Maria Mo-rahan, Isabel Tsverik. Paediatricians: Melanie Bracewell,

Michele Cruwys, Ruth MacGregor, Lesley McDonald,Margaret Morton, Margaret Morris, Sue Thomas. Muth-

anna Samara (Psychological data analysis), Heather Palmer(Study Administrator).

Funding: BLISS, PPP Foundation and WellBeing.The EPICure Study Group comprises the paediatri-

cians in 276 maternity units across the UK and Ireland whocontributed data to the study, whose invaluable help weacknowledge. The investigator group was responsible for theoriginal study cohort identification and studies up to 2.5 years

of age and the developmental panel performed the data col-lection and validation.

Specific Language Difficulties and School Achievement in Children Born at 25 Weeks of Gestation or Less 262.e1

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Speciﬁc Language Difﬁculties and School Achievement in Children Born at 25 weeks of gestation or less