At risk for language disorders? Correlates and course of languagedisorders in preschool children born at riskD Weindrich1, Ch Jennen-Steinmetz1, M Laucht1, G Esser2 and MH Schmidt1

Central Institute of Mental Health1, Mannheim, Germany; University of Potsdam2, Potsdam, Germany

Weindrich D, Jennen-Steinmetz Ch, Laucht M, Esser G, Schmidt MH. At risk for language disorders?Correlates and course of language disorders in preschool children born at risk. Acta Pædiatr 1998; 87: 1288–94. Stockholm. ISSN 0803-5253

The language abilities of 324 children of an at-risk population were investigated at age 2 and 4.5 y. Modifiedresearch criteria of the ICD-10 for specific developmental disorders of speech and language were applied.Frequencies between 4% and 7%, depending on age and type of disorder, were diagnosed among childrenwhose performance on the language measure was only 1 instead of ICD-10’s 2 SD below group mean, but thediscrepancy measure of 1 SD between non-verbal language score and language measure was retained.Psychosocial aspects of a child’s environment proved to be better predictors of later language disorders thanobstetric complications. Stability of specific language disorders was on the whole fairly low, but childrenwho perform below age level on language measures remained at risk. Gender differences are almostcompensated by the age 4.5 y.` Biological risk, preschool age, psychosocial risk, specific languagedisorders

Diana Weindrich, Department of Child and Adolescent Psychiatry and Psychotherapy, Central Institute ofMental Health, PO Box 122120, D-68072 Mannheim, Germany

Children at risk for developing a language disorder havebeen the topic of several longitudinal studies worldwide inthe past decade (1–3). The identification of relevant riskfactors to facilitate early diagnosis and prognosis of poten-tial or manifest disorders is at the heart of these efforts. Twomethods are open to the researcher. Either a longitudinalprospective design is chosen, in which a group of infantsborn at well-documented biological risk is followed frombirth through childhood with assessment of, among others,language development at different intervals along the way.Or, in a case-control setting, a group of children withdelayed language development, the referral group, and acontrol group are identified and reassessed over time. Bothmethods have drawbacks: In prospective studies thenumber of children with certain disorders may be toosmall to allow detailed analysis or conclusions on therisks factors. Biological risks are often well defined,environmental risks much less so. The latter, however,have proved to be more important in language development(4–6). Therefore, the evaluation of the effect of certainbiological risk factors may be contaminated by their inter-action with environmental variables. On the other hand,within a case-control setting it is often not possible tovalidate surmised or reported perinatal complications andtherefore todrawconclusionsconcerningtheirconsequences.Because of these and other reasons it is often difficult tocompare the results of studies which have been publishedabout the risk factors involved in language disorders.

The effect of organic risks, i.e. the sequelae of pre-, peri-and postnatal complications, is purported to be negligent

(4, 7, 8). Research shows that their effect is not specific butgeneral in nature. Psychosocial risks are considered, if atall, to be important as mediating factors in the genesis oflanguage disorders, that is, are responsible for perpetuationbut not causation of a language problem. Genetic aspects oflanguage disorders discussed elsewhere (9–11) will not beconsidered here since neither a prospective longitudinaldesign such as ours nor the case-control method but onlystudies with twins, adopted children or family studiessuffice to clarify the issue.

The evolution and application of internationallyaccepted diagnostic criteria of existing disorders shouldmake it easier to evaluate and compare results of thecontributing research groups. In the ICD-10 (12) as wellas DSM-IV (13), criteria are spelt out for the diagnosis of‘‘Specific Developmental Disorders of Language andSpeech’’ (ICD-10) and Communication Disorders (DSM-IV). The diagnostic guidelines are similar in regard toexpressive, receptive and articulation disorders. In allcases a child’s score on a standardized test of the develop-mental language measure in question must be substantiallylower than his or her score on a standardized non-verbalintelligence test, as well as below age group. Thus a child’slanguage abilities are assessed in terms of his or her ownintellectual capacity as well as in reference to average ageperformance of peers. However, with the help of thesecriteria only the core group of children with acute impair-ment can be identified. For clinical work it is usually ofequal importance that all children with a delay be diag-nosed and treated. Although the discrepancy model of

Acta Pædiatr 87: 1288–94. 1998

q Scandinavian University Press 1998. ISSN 0803-5253

cognitve-language relation has been challenged as to itsstability and efficiency in determining who should receivetreatment (14), it is used here to identify specific riskfactors of delayed language development.

The work presented here is concerned with the role ofspecific risk factors in a German population and the stabi-lity of specific language disorders. As part of a prospectiveproject, ‘‘The Mannheim Study of Risk Children’’, it ispossible to examine the long-term effect of well-defined,organic and psychosocial risks on language development ina group of German children born between 1986 and 1988who were followed from early infancy to school age.

MethodSubjects

The subjects in this investigation are participants in theMannheim Study of Risk Children, a longitudinal projectfollowing infants at risk for later developmental disordersfrom birth to school age. Depending on pregnancy and birthhistory and on familial background, infants were assignedto one of nine groups resulting from a two-factorial (3× 3)design with factor I representing the degree of biologicalrisk and factor II the degree of psychosocial risk (eachscaled as no risk, moderate or high risk). A total of 362infants born between February 1986 and February 1988were recruited from two obstetric and six children’s hospi-tals of the Rhine–Neckar region (Germany). All groupsare about equal in size, with a slight oversampling in thehigh-risk combinations and sex evenly distributed in allsubgroups. Only firstborn singletons of German-speakingparents who had no severe physical handicaps, obviousgenetic defects or metabolic diseases were selected.

Biological riskwas defined by the degree of pre-, peri- orneonatal complications: (i) the non-risk group includedonly full-term infants who had normal birthweights andno medical complications; (ii) the moderate-risk groupconsisted of infants with preterm births or preterm laboursor EPH gestosis of the mother; and (iii) the high-risk groupof infants met the criteria of very low birthweight, clearcase of asphyxia with special care treatment or neonatalcomplications such as seizures, respiratory therapy orsepsis (for detailed definitions, see 15).

Psychosocial riskwas determined according to a riskindex measuring the presence of unfavourable familialcharacteristics. The 11 items of this index cover low edu-cational level of the parents, crowded living conditions,parental psychiatric disorders, parental delinquency orbroken home history, marital discord, early parenthood,single-parent family, unwanted pregnancy, lack of socialsupport, severe chronic difficulties and poor coping skills(for precise definitions see 15). A total of 115 infants wereassigned to the non-risk group (with a score of 0), 102infants to the moderate-risk group (score of 1 or 2), and 107infants to the high-risk group (score of 3 or more).

The subsample reported on here refers to the investiga-tions at 2 and 4.5 y and differs from the study sample in that

the data from children with severe motor or mental handi-caps (IQ or MQ, 70) and/or a frank neurological impair-ment were eliminated. A total of 324 children, 158 boysand 166 girls, evenly distributed across the risk groupswere assessed. These children had passed the screeningtest for hearing and none had been diagnosed as autistic.

Assessment

To measure non-verbal intellectual capacity at 2 y, selectednon-language items from the Bayley Scales of InfantDevelopment (BSID) (16, 17) were chosen. At 4.5 y theColumbia Mental Maturity Scale (CMMS) (18) was admin-istered. At 2 y expressive language was assessed as the sumof selected expressive language items from the BSID andthe scale of expressive speech of the Munich Developmen-tal Scales (MFED) (19), receptive language as the sum ofselected receptive language items from the BSID and thereceptive scale of the MFED. At 4.5 y the subtests ‘‘Gram-matic Closure’’ (GC) and ‘‘Auditory Closure’’ (AC) fromthe Illinois Test of Psycholinguistic Abilities (ITPA) (20)were used to assess expressive and receptive languageskills respectively. (Although the theory of child psycho-linguistic functions underlying the ITPA is based on ahierarchical factor model of 12 subtests, single subtestshave proven useful as screening measures in test batteriesinvestigating certain domains of language (21)). Articula-tion, only at age 4.5 y, was measured using the Mo¨hring test(22). All instruments, with the exception of the Mo¨hringtest, have been widely used internationally. German normsare available for all instruments except the BSID. This wasremedied by using a representative subsample for determi-nation of cutoffs as described below. The speech tests hadalso been shown to be effective in the diagnosis of specificlanguage disorders in another recent German study of 8-y-olds (23).

The two best known classification systems, ICD-10 andDSM-IV, give similar definitions of ‘‘Specific Develop-mental Disorders of Speech’’ (ICD-10) and ‘‘Communica-tion Disorders’’ (DSM-IV) for different types of disorders.The guidelines were referred to for diagnosis of expressive,receptive and articulation disorders. Operationalization ofdisorder types followed the ICD-10 procedure with a minormodification. Instead of 2 SD, only 1 SD below age groupwas required for the language measure. The modificationwas necessary since only very severe language disordersmeet ICD-10 criteria, but not the clinically more relevantcases. Aspecific language disorderis defined by thefollowing diagnostic criteria: (a) the performance on thelanguage test was at least one standard deviation (SD)below the group mean, (b) the measure on language per-formance was at least 1 SD below the non-verbal IQ score,(c) the non-verbal intellectual capacity was not less than2 SD below group mean, and (d) when diagnosing anexpressive language disorder, the test score on the recep-tive measure was not less than 2 SD under the group mean;for an articulation disorder neither the score on the recep-tive scale nor the score on the expressive scale should be

ACTA PÆDIATR 87 (1998) At risk for language disorders? 1289

lower than 2 SD under the group mean. Furthermore, anexpressive disorder is not diagnosed in the presence of areceptive disorder. An articulation disorder may only bediagnosed if neither an expressive nor a receptive disorderis present. Thus there is no overlap between disorder types.Children with more than one impairment are classified inthe next highest group in the order receptive, expressive,articulation. For descriptive purposes we also provide thefrequencies for the original ICD criteria and for a furthercriterion which we calldelay. A delay was defined as alanguage score at least 1 SD below group mean withoutreference to intelligence. For determining the disorders,cutoff values must be set which are calculated from meansand standard definitions of language and non-verbal intel-ligence scores. These were taken from a subsample of 110infants (55 boys and 55 girls) who were representative ofthe birth cohort of the region with respect to sex, birth-weight, referral rate and socioeconomic status. Fisher’sexact test was used as the statistical method for the analysisof language disorders.

ResultsFrequency of language disorders according to differentcriteria and gender

The frequencies of language disorders are compared in

Table 1 in accordance with (a) ICD-10 research criteria,(b) the modified definition, and (c) the delay criterion. Boththe ICD-10 and the DSM-IV quote prevalencies for lan-guage disorders in the range of 3–5% in a general popula-tion. Even though our sample includes a large number ofchildren born at risk, the frequencies obtained by the ICDdefinition ranged only from 0.6% to 3.7%, depending onage and type of disorder. According to the modified defini-tion of specific language disorder, frequencies rangedbetween 4% and 7%. The highest rate, namely 7.4%, wasfound for receptive disorders at age 4.5 y. Similar preva-lence rates have been reported for expressive and receptivedelays among 3-y-old and 5-y-old children using similarless stringent research criteria (24, 25). As expected, thepercentage of delayed children was much higher than thepercentage of children with a specific disorder. Thus, therewas a noteworthy group of children who were delayed inlanguage skills but did not deviate as required from theirintellectual capacity to fulfil the discrepancy criterion ofthe specific language disorder.

Table 1 also gives the number of boys and girls with aspecific language disorder. The percentage of boys with alanguage disorder was higher than for girls and is statisti-cally significant for expressive disorder at age 2 y andarticulation disorder at age 4.5 y (p , 0:05, Fisher’s exacttest). These findings support data presented previously inthe literature (2, 26).

1290 D Weindrich et al. ACTA PÆDIATR 87 (1998)

Table 1.Frequency of language disorders according to different diagnostic criteria and gender.

2 y 4.5 y

Total Girls Boys Total Girls Boys(n ¼ 324) (n ¼ 166) (n ¼ 158) (n ¼ 324) (n ¼ 166) (n ¼ 158)

n % n % n % n % n % n %

Expressive DisorderSpecific Language Disorder 12 3.7 1 0.1 11 7.0 2 0.6 0 0 2 1.3(ICD-10 research criteria)

Specific Language Disorder 18 5.6 4 2.4 14 8.9 14 4.3 6 3.6 8 5.1(modified definition)

General Developmental Delay 28 8.6 8 4.8 20 12.7 20 6.2 7 4.2 13 8.2(performance below norm)

Receptive DisorderSpecific Language Disorder 2 0.6 0 0 2 1.3 4 1.2 1 0.1 3 1.9(ICD-10 research criteria)

Specific Language Disorder 13 4.0 4 2.4 9 5.7 24 7.4 11 6.6 13 8.2(modified definition)

General Developmental Delay 37 11.4 11 6.6 26 16.5 36 11.1 14 8.4 22 13.9(performance below norm)

Articulation DisorderSpecific Language Disorder – – – – – – 6 1.9 1 0.1 5 3.1(ICD-10 research criteria)

Specific Language Disorder – – – – – – 23 7.1 6 3.6 17 10.8(modified definition)

General Developmental Delay – – – – – – 24 7.4 7 4.2 17 10.8(performance below norm)

Course of specific language disorders from 2 to 4.5 y

Figures 1 and 2 show the stability of specific languagedisorders from age 2 to 4.5 y. Three of the 18 children witha specific expressive language disorder at age 2 y (16.7%)retained the disorder up to age 4.5 y, whereas only 11 of306 (3.6%) children were newly diagnosed with an expres-sive language disorder at age 4.5 y. This difference isstatistically significant (Fisher’s exact testp, 0.05). Forreceptive disorders the stability was 23.1% versus 6.8%newly diagnosed at age 4.5 y, which is not statisticallysignificant. The stabilities (16.7% for expressive and23.1% for receptive disorders) seem rather low. However,this does not mean that the rest performed at age level onthe language tests at 4.5 y. In fact, some of these children(22% and 15%) remained below age level with respect tolanguage skill, but were not now diagnosed with a specificdisorder since the discrepancy criterion was no longerfulfilled or, in the case of an expressive disorder, werenewly diagnosed as having a receptive disorder. Furtheranalysis revealed that stability of children with delay was21.5% for expressive and 40.5% for receptive languageperformance from 2 to 4.5 y. These results correspondroughly with those of Silva et al. (25). Higher stabilities(about 50% for an expressive delay) for language delayfrom 2 to 3 years were reported by Paul et al. (27).

Impact of organic and psychosocial risks onlanguage disordersAn analysis of the proportion of children with a specificdisorder in each of the three organic risk groups revealed

that the effect of organic risk was, on the whole, fairly weakand statistically not significant. The same is true of psy-chosocial risk. An analysis of the combined effect oforganic and psychosocial risks would be of interest. Butdue to the overall low incidence of specific language dis-orders the number of language disordered children in thenine cells of the design was too small for statisticallyreliable conclusions. A further analysis pertains to theeffect of single risks. As mentioned above, the riskgroups are made up of children with diverse risk factors.A list of these risks is given in Table 2. The effect of eachrisk on language disorders was analysed separately. Chil-dren with a specific organic risk were compared to childrenwithout any organic risk. The same procedure was fol-lowed for the psychosocial risks. Table 2 shows the ‘‘rela-tive risk’’ of developing a specific language disorder foreach single organic risk factor. A relative risk is the statis-tical term for the quotient of two rates; for example, the rateof children with a language disorder among children with aspecific organic hazard divided by the rate of children witha language disorder among children without any organichazard. As already discussed, the overall effect of organicrisk was low. This may be seen again in the analysis of eachsingle organic risk. These effects are weak and statisticallysignificant only for the factors ‘‘premature birth’’, EPHgestosis and ‘‘high lactate level’’. A relative risk of zeromeans that no child with the particular organic or psycho-social risk had developed the language disorder. The resultsshould be interpreted cautiously, especially for the risksapplying to only a small number of subjects.

The lower half of Table 2 gives the relative risks of thepsychosocial risk factors which clearly had a more specific

ACTA PÆDIATR 87 (1998) At risk for language disorders? 1291

Fig. 1. Course of expressive disorders between 2 and 4.5 y.

1292 D Weindrich et al. ACTA PÆDIATR 87 (1998)

Fig. 2. Course of receptive disorders between 2 and 4.5 y.

Table 2.Effect of organic and psychosocial risk factors on specific language disorders: number of children with certain organic or psychosocial risks (n)and relative risks for developing specific language disorder.

2 y 4.5 y

Risk factor n Expressive Receptive Expressive Receptive Articulation

Organic RiskPremature birth (,37 weeks) 167 0.8 0.8 2.2 2.8 1.3EPH gestosis 45 1.7 0.0 4.1* 1.9 1.1Birthweight#1500 g 34 0.5 0.0 4.4* 0.8 0.9pH #7.10 8 0.0 2.8 0.0 3.5 0.9Lactate$8.00 mmol/l 9 4.1 0.0 4.1 12.5*** 0.8CTG score (Fisher)#4 20 0.9 0.0 0.0 0.0 0.8Respiratory therapy 49 1.1 0.0 3.0 2.3 1.0Seizures 8 4.7 0.0 4.7 7.0 0.0Neonatal sepsis 15 2.5 1.5 5.0 1.9 1.1

Psychosocial RiskLow educational level of parents 57 1.2 16.1*** 2.0 2.5 0.8Crowded living conditions 25 0.0 13.9* 4.6 2.3 0.9Parental psychiatric disorder 62 1.6 11.1** 4.6 4.6** 0.6Delinquency/institutional care of parents 63 1.0 7.3 4.6 2.7 0.9Troubled relationship 37 0.9 3.1 3.1 2.3 0.9Early parenthood 79 1.0 8.8* 1.5 4.4** 0.7Incomplete family 32 1.0 3.6 1.8 5.4** 0.4Rejected pregnancy 46 1.1 5.0 1.2 1.9 0.5Lack of social integration 13 2.5 8.8 8.8* 4.4 0.9Severe chronic difficulties 89 0.4 7.8* 2.6 2.3 0.9Lack of coping skills 120 1.0 4.8 2.9 2.6 1.1

+Significance according to Fisher’s exact test.*p , 0:05; **p , 0:01; *** p , 0:001.

effect on language disorders than the organic risks. It is noteasy to rank the separate risk factors, because their role isnot the same for each type of disorder. The overall mostimportant factors were ‘‘low education level’’ of a parent,‘‘psychiatric disorder’’ of a parent, ‘‘early parenthood’’,‘‘incomplete family’’ and ‘‘lack of social integration’’.The significance of psychosocial risk factors, especiallyeducation level of father as the foremost indicator offamilial socio-economic status, has been reported else-where (28, 29). Surprisingly, problems of receptive lan-guage were more highly correlated with psychosocialrisk than expressive disorders. The postulated effect ofbirth order may be discounted since all children in theMannheim Study of Risk Children are first born.

DiscussionApplication of modified ICD-10 research criteria for diag-nosis of specific language disorders in 2-y-olds and 4.5-y-olds of a risk population yielded, depending on disordertype and age, frequencies of 4–7%. A specific languagedisorder was diagnosed in children whose performance onthe language measure was only 1 rather than 2 SDs belowgroup mean, as required by the ICD-10, but the discrepancymeasure of 1 SD between non-verbal IQ and languagemeasure was retained. There were two reasons for doingthis. For one, it is of interest to look at the substantialnumber of children with less severe language disordersthan diagnosable by the ICD-10 criteria. This is an impor-tant clinical consideration and also crucial when followingthe course of development of a risk population. Only timewill tell which of these children retains or eventuallymanifests developmental problems as a result of early orpervasive risk factors. The second reason has to do with thelanguage measures available for this early age group. It isdifficult to differentiate enough at the lower end of theselanguage scales. The diagnosis of a language disorder maybe dependent on the performance on only a very few items.The least stringent criterion, namely for children with adelay, whose performance on the language measure was1 SD below group mean, but did not fulfil the discrepancycriterion between language measure and a non-verbal IQ,yielded the highest rates of 6–11%.

As in other studies our results show that boys appear tobe biologically more vulnerable for language problemsthan girls. This is especially true for expressive languageat age 2 y. Obviously, there are a number of ‘‘slow lear-ners’’ among the boys. By age 4.5 y these effects are almostgone. A sex effect is found only for an articulation disorder.

Stability of language disorder proved to be rather low.However, there is a strong probability (21.5% and 40.5%)that children with a delay (discrepancy criterion notrequired) would remain below age level in both areasfrom 2 to 4.5 y.

One of the main advantages of the Mannheim Study ofRisk Children was the possibility to examine the role ofspecific, well-documented organic and psychosocial risk

factors as correlates of specific language disorders. Theresults show that the overall effect of organic risk as well asmost of the single risk factors are low and do not reachsignificance. Within our research group, effects of organicrisk on general cognitive development have been shown(15). Apparently, organic risk is not per se a precursor ofspecific language disorders but may have an effect ongeneral cognitive performance. A similar conclusion wasreached among others by Aram et al. (30) with a sample ofolder very low birthweight (VLBW) children. Languagedelays were no more common among the VLBW thanamong control children although the former were moreoften diagnosed with a combination of developmentalproblems.

On the other hand, various single psychosocial risksappeared to be related to specific language disorders. Sur-prisingly, most of them pertained to receptive disorders.This may reflect differences in measurement and/or identi-fication of the disorders. The foremost risks associated withlanguage disorders were, as in other studies, low educationlevel of parent, psychiatric disorder of parent, early parent-hood, incomplete family, lack of social integration andsevere chronic difficulties. At first glance, these are risksassociated with a disrupted youth of the children’s parentscombined with social isolation. The importance of parentsas role models to facilitate acquisition of language, asconcerned monitors of developmental milestones and asresponsible persons in overseeing treatment, underline theareas in which the presence of risk factors may operate tohamper language development on the whole. At secondglance, some of these risks, such as low education level andpsychiatric disorder, may also be interpreted within a frameof family history. On the basis of our design it is notpossible to decide whether the genetic or psychosocialcomponents of the risk factors are responsible for thelanguage disorders of the children.

Some practical consequences may be drawn from thisresearch. Results showed that stability of specific languagedisorders from 2 y to 4.5 y is low. This does not mean thatthese children ‘‘catch up’’ by 4.5 y. In fact, some of themstill perform below age level, but the discrepancy betweenlanguage and non-verbal intelligence is no longer greatenough to diagnose a specific language disorder. Thereforeall children performing below age norm warrant profes-sional attention. By 4.5 y at the latest, therapy should beinitiated. The discrepancy rule might come into play here.In the case of a specific language disorder, treatment in theform of speech therapy would be advised. Children with ageneral developmental delay would be referred to remedialtherapy. At any rate our results support the observation thatwhile some children catch up on language skills othersneed help before entering school. The children with theleast favourable prognosis would be according to our workthose with specific or a constellation of unfavorable psy-chosocial risk factors. Of great interest will be the furtherdevelopment of these children at school age and the role ofearly language impairments for later reading and academicdifficulties.

ACTA PÆDIATR 87 (1998) At risk for language disorders? 1293

Acknowledgments.—This project is supported by a grant from theDeutsche Forschungsgemeinschaft as part of the Sonderforschungsber-eich 258 ‘‘Indicators and risk models of the genesis and course of mentaldisorders’’ at the University of Heidelberg, Germany.

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Received Jan. 29, 1998. Accepted in revised form Aug. 4, 1998

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