Play and Language in Developmentally Disordered Preschoolers

Play and L~ngpage in Developmentally Disordered Preschoolers: .. ~·NewAppro~ch to Classification '. MIRIAM $¥E~:M:AN, M~D.;THEODORE SHAPIRO, M.D.,

AND

MARC'GLAS$¥AN, PH.D.

Twotelatedtes~ar
tism, investigators have attempted to classify, clarify and qerive subgroups of those children with abnormalities of social interaction, behavior, language and imagination. This has led to a confusing array of labels,' such as "childhood psychosis," "atypicality," , "childhood schizophtenia'HBerider, 1942), "symbiotic psychosis" (Mahler, 1952)~aJid ha.s culminated most recently in·thecurrenl'DSM-IIldassification "per-. vasivedevelopmentaJdisorde~i'(PJ:)D) which is an atteinpt to categorizedisordets based on observable deviance in behavior. , Many. developmentallydisordered preschoolers;'es'pecially those with autistic featUres, do not "fit" easily intothecurrent diagnostiC categories because of a lack of clear distinction among DSM-III categories or because of a spectrUm of deviance not easily accounted for within each category. Also, each DSM-Illsyndromem,ust be judged in a categorical "yes" or "no" fash.ion withbut consideration' for partial syndromes. Prior investigators studied children who fit Kanrier's (1943) restrictive description of autism because they believed'autism to be a separate entity that is categorically·different from the lar~er group of deyelopmentally disordered children. More recently, how~ ever, investigators (Freeman•• et.aL,··•. 1981; Wing,.1981; Wing and Gould, 1979) have provided new data th~t call into question not only the sepa.rateness of autism but the uniqueness of PDDandsciggests its overlap with other diagnostic groupings such as mental1'etardation when it is associated with social deviance. Based on their epidemlolog{c~tudY'()f'children with the triad of impairments ofsocial interaction, COmmllnication and imagination~'Yingand Gould (1979) recommend that no clear distirictiorts exist that make a .difference. between children classified as having Early Infantile Autism and those classified in other categories. There is general agreement that disturbance of sym511

512

SHERMAN ET AL.

bolic functions as revealed in play and ianguage constitute a central feature in many developmentally disordered· children.. Indeed, prognosis for .classically autistic children has been related to one symbol system-language-along with IQ,total symptom score and severity (Rutter, 1971). Thus far, the few studies of play in autistic children recorded in the literature have focused primarily.on a single area of play-,,-symbolic or pretend play using scales based on Piagetian cognitive principles· (Piaget, 1962). Kanner (1943, 1973) described theabserice of symbolic play to be one of the clinical features of Early Infantile Autism. Lowe (1975) established developmental trends in representational arid symbolic play in normal infants from age 1 to 3 years. More recently, Wing et al. (1977) highlighted the association of impaired symbolic play that was also fourid in a group of mentally retarded school-age children having a mental age less than 20 months. . The scant formal data on play of preschool disordered children is mirrored by the few instruments that have been developed to measure,and evaluate the more varied parameters than have been previously considered. Theorists have wolldered ifearly symbolization in normal and disordered children is "of a piece" such that skill in one symbol system implies or. correlates strongly with other symbolic systems such as language, Indeed, one may question whether the traditional distinctions between play and language are atbitrary and relate to m!'lturationallevel. For example, play and. language may both be subsumed under a more general symbolic faculty and both may also be a feature of developing social behaviors as well as cognitive skills. While each may be studied as discrete developmental lines, their iritercorrelation may reveal a hypothetical guiding pilot that drives all symbolic activity. In contrast to play research, language behavior has been studied extensively in disordered children. It has been determined that autistic children have difficulty in any. designative.: function· that requires complex semantic coding and in the practical application of language to interPersonally appropriate messages (Cromer, 1981; Curtiss, 1981; Tager-Flusberg, 1981). Prognosis for these. children has been shown to be significantly related to the degree and pattern of productive deviance rather than merely to linguistic retardation (Shapiro et a1., 1970, 1974; Shapiro and Fish, 1969). The association of molar measures of language .and play has been addresseQ, in other investigations by Tilton and Ottinger (1964) and Wing et a1. (1977). More recently, Ungerer and Sigman (1981) studied 16 autistic children using more molecular techniques formerly used to study Down's syndrome children (mean

age 51.7 months) comparing play behavior to language comprehension. As expected, higher language comprehension correlated positively VVith increased levels of functional and symbolic play. In this study a broadened conceptual definition of play was used and was operationally defined to include object use, symbolicability,'d.iversity of interests and peer interaction. Such a multidimensional focus permits testing of the relationship of parts of the whole to linguistic and other measures of impairment and deviance.

Method Play and language behavior and functional status were studied in a group of developmentally disordered preschoolers ranging in diagnosis from pervasive developmental disorder to mental retardation. We wished to determine if both play and language behavior are valid indicators of current functioning. In order. to study this question, .new play and language assessment measures were tested for· validity against multiple performance indicators of functional severity. SUBJECTS

Subjects. were 48 developmentally disordered preschoolers (39 boys, 9. girls) ages 2-5 ye8.rs (26-62 months; mean 47.9 months) drawn from two therapeutic nursery programs in New YorItCity. All subjects had disorders which included a spectrum of communication deficits, social withdrawalandretardation and were considered unsuitable for normal nursery programs. Performance IQ, DQ and mental ages were derived from Gesell Developmental Schedules (Gesell and Amatruda, 1941) and the Merrill~PalmerScale of Mental Abilities (Stutsman, 1948) ranged from mental age 12 to 48 months (mean: 21 months); performance IQ ranged from 30 to 90 (mean: 60). PROCEDURE

Each child was assessed clinically upon admission to the nursery. The assessment included individual evaluation of 1-2 hours in. duration by a child psychiatrist' examination of all prior medical and psychiatric records, psychological testing that included assessment of language comprehension and administration of the Gesell and Merrill-Palmer developmental tests by a psychologist. For 30 children, all data were presented to two child psychiatrists who independently made diagnostic assessmentsbased upon current DSM-III criteria. Following these evaluations; two other independent child psychiatrists observed each child's behavior and play during a 30-min period in the child's regular classroom with teachers and peers. The behavior and play indicators which will be outlined in the following section

PLAY AND LANGUAGE

513

tually distinct aspects of play behavior and one la~­ guage comprehension ';measure that includes items adapted from existing norms regardingcomprehenINSTRUMENTS sion instruments (GeseUDevelopmental Schedules and Stanford-Binet (Terman and Merrill,·1960). Functional StatltS The fourcli~icalratings tap aspects of play behavior ;'Functional status," as operationalized in this which seem clinically meaningful in this population: , " study, is assessed by three meaS\Ire~: 1) the Behavior 1) ",Object Use," (2) "Symbolic· Play," 3) "Diversity of Checklist for,Disordered Preschoolers, 2) a global Interest," and 4) "Peer Interaction." Again, two inder~ting of levelof functional impairment, and 3) an IQ pendent assessments made by child psychiatrists are test. available on 30 preschoolers. Intraclass correlations The first measure, the Behavior Checklist for Dis-, were computed on each of the four sets of play ratings. ordered Preschoolers (BCDP, Appendix I) isa prelimThese agreement statistics rangedfromalow of0.84 inary version of a rating checklisto(29 items which for "diversity of interest" to a high of 0.93 for "sym~ taps'the "sampling domain" ,of general behavioral bolic play." "Qbject' use~'l;lnd ,"peer interaction" functioning, e.g., relatedness tpother people, relatedshowed intraclass correlations between these two exne~s to physical surroundings, motor disturbances and tremes: 0.86 for object use a:qd 0.91 for peer interaclanguage iInpairment. < ' ", ' tion. " Although, the jqstrument is ,still being developed, The language comprehensio,n test was administered preliminary data relevant to its psychometric prOPlilrby a psychologist and shows a very strongpositiye ties' exist Two psychiatrists independently rated a ,correlation with an independ~nt measure of language subset of 30 children using the 29-item rating checkcomprehension (Gesell Developmental Schedule), r = list. Throughminor modifications in its, computa0.93 (p < 0.001). In light of these correlations, there tional formula, the intraclass correlation coefficient seems to be satisfactory evidence for the, prelilllinary can be used to evaluate inter-rater,agreement (Shrout reiiability of these measures. With regard tothe valid',and Fleiss, '1979). As this statistic departs, from a ity of thisconstrtlct, a factor analysis of the five ~;,' maximum value of 1.00, indIcating perfect agreement, indicators suggests the presence of a single,underly:ing . ' the raters increasingly disagree in theirjudgDlents. In empirical dimension, i.e~, a "play and langua~e~-conthis case, inter-rater agreementis' 0.90. In terms of struct. This finding suggests that the clinicaldistincvalidity, the subset .of, language items in the checklist, tions drawn refer to "aspects",of one empirical dimencorrelates substantially with,an independentmeasure sion rather than to four independent empirical dimenof ,languagecl.evelopment, the Gesell Developmental sions. The internal consistencyreliapility of this diSchedules; 0.65(p ~0.001). One ofthe. primary '~ension as measuredhy Cronba,ch's alpha (u) coeffipurposes ofthis paper is to test for ,additional evidence cient is 0.92. In interpreting the factor analytic results, of, 'Validity, for the behavior checklist anci the, Global the reader should note that although eac4 area is Sevel'ity Ratingoutliriedbelow. . , . operationalized as a single item, in actuality it reflects The second measure, the GlobaLSeverityRating, is a comprehensive clinical evaillati
r=

514

SHERMAN ET AL.

. ". Results ." . measured by these instruments; does not necessarily' .. The an~lysispresented attempts to assess the utility· imply behavioral or functional equivalence: Children . with identical diagnoses can aIiddo varysubstantiall{ . of various aspects of plaY' and language behavior as · in their functional severity. As 'such,diagnosis asa ~ndicators Of the current furtctioning ofour Sample of categorical statement with the consequent substantial . developmentally disordered children. ClinicaldiagnoWithin-group variability which its use would imply sis might logica1ly serve as a basis for dasSifying these . could'confound the evaluation'of play and language ., children into functionally homogeneous groups which 'behavior as indicators of impairment. In view of this, '. could then be used to test the criterion validity ofthe more functionally' homogeneous groupings were de:: , play andlanguage measures~ The rationale for using veloped .via clustering·;procedures.· . diagnosis as' a classificatory criterion is' provided by numerous' observations which indicate that autistic CLUSTERS children manifestless··."relatedness":and more ritualClustering is.a.dataarialytic technique thatparti"· ized behavior than do mentally retarded children. In ·tions objects into subgroups based upon the similarity "addition, clinical observation strongly suggestsevi~f scores ona seiof classifying variables. In this dence of poorer cominunic~tive language development application, a childis assigned to a "cluster" or group . among autistiC children. of children with whom he/she is most similar as Our data provide further support for these obsermeasured by his "proflle" of ~coreson the clustering vations(seeTable 1). In particular, the autistic group variables, here: 1) Total i3ehavior.C1J,ec~ist Score, 2) .... ofp~eschoolersmanifests sigffificaIitry less peer interRatir4J, and 3) IQ or adaptiveDQ. The Global Severity .action .·and diversity of interest than" do the mentally threevariables used. for clustering were chosen in .retarded children. In addition, the observed difference' accord with what is knoWIl. cliriically'tObethe slgnif- . in language comprehension between the two groups, icantpararileters of functional prognosis. The.·result~ 'although not statistically' significant, does indicate antd1isters arenbtonly as functi6rially homogeneous '.lower levels of linguistic· development among the aubut these groupings areasdiffet.ent, vis~: as possible, tistic group of children. In 'general, then, these data a-vis eachothE;lr,as possible~ The actual number of' do suggest that clinical diagnosis is a possible, algroupings oftlusters derived is determined. by th~ . •. though we argue not a preferable'basis for categorizing nature of the application. (The ~riterionused hi these ... . disordered children. . analyses involves inipiinizing the "distatice"of each The basis for our reservation is the rather substan·case from thecepter of the cluster to which the case tial amount of within diagnostic'group variability with is .assigned' at each stage" in. the clust~ringptocess; regard to global assessment variables such as the Total This type. of algorithriiis a representative type'of Behavioral Checklist Score, Global Severity Rating, clustering algorithm. It is generically known as kand IQ. It seems dear that diagnostic equivalence,as means algorithm (Hartigan, 1975) whichcontinuo\1sly "updates" the dusters' m(:lmbershipsat each stage of TABLE 1 thedusteringprocess. In. doing, it shouidmihiriiize Means arul Standard Deviations of 4 Play, 1 LangUage, and 3 the degree of dIssimilarity amongclustetmembersat Global Assess~nt Measures by Cli~icafDiagriosis" each stage Oflhe ·clusteringi>ro~ess.) . .- -:,"-.. .Merttally In this stlIdy, 2-,3:,'4" ;and 5~clustersolutions were' A~tistic . Retarded ., ..' Measu,re (ti ~.16).· (N = 22) examineq. rplienecessity for. examining (li'tfer~rit'levels' clustering is based on the' desirapility: of forming . Mean so·' Mean ·so. pb. groupings' which are I19tonly empir~c8J.ly homogelle~ 3.38 1.06 ~.'71 1.37 sO.215 ObjectS· bUS, but also cliiiicallymeaningfUl.'Table 2 presents . Symbolic' '1.64 0.89 2.87 L54 ::sO.003 the' standard deviations ofeach chlsteriilg variable for PeerS' . '3.44.'1.32 '4.77 1.57 ::so.ool· the four·soliiiions. . Diversity" 2.~3 0.89 3.23" 0.97 ::sO.oOl Language Comp.d . 25;50 10.62 .30.73 14.31 ~O.113 As the diitai:indicate,both-:the;2~-and"3-Cluster solutions· contain·considerablewithiri.-cluster hete~o­ BCDP Total' . 46.00 14.45n96.15.98::s0.oo1· Global Sev. Rating' 4.690,87 3.~4·1.67.::S0.ooL· gEmeity on the total s0nptom score and, to a lesser IQ 6~,1?: 16.54 ~7.68.15.82-e:0:055 extent, IQ;lIlview ofthis fa~t, a liigherlevelsolution . .' "Ten children with. ~atypiclll~.diagnoses (N=6) or langullge seems to be require&Again;as m()re clusters are qisorders (n';' 4) have been excltided,; . derived the groups will tend to increase in homogebUnivariate F test. . neity with regard to their functioning:,·' ' . . 'Reversed Scoring: higher scores imply less impairment. The 4-cluster solution'incre~ses the llomogenElityof dLanguage Comprehension 8core;months. . thEl clusters with regard to behavioralsympt()mat()logy 'Behavior Checklist for'Disordered Preschoolers, total score. ./Global Severity Rating. and severity, but doesn~t consistently.reduce the

a

so

or

515

PLAY AND LANGUAGE

TABLE 2 .' Stalidard Deviations of Behavior Checklist for Disordered Preschoolers (BCDP)-Total Score, Global Severity Rating, and IQ for Various '. '. .,. Cluster Analytic Solutions . . .' Cluster 4

.5

9.21 1.10 8.27 (n = 14) 8.14 1.07 6.02 (n

= 11)

7.67 .0.90' 10.51

(n:= 16) 6.73 ' . 1.02 .

9.53 (n = 1,5)

'7;60 1.07 5.74

(n=9)

o Eoily Inlanlile autismln=16) withiri-clusterheterogeneity of IQ. In'particular, clus. ", • . Alypi~cil. p~rvaslve develapmental dlsarder (n~IO) Totol n=48 ter 2· in the 3-cluster solution is left intact in the 4. ~ MenIal relardaliail (n-22) . cluster solution, Since this cluster's heterogeneity in '. IQ remains consi<;lerable, a 5~cluster solution was ex- .' 40 a.~ined. . ." .', . 30 The5-cluster solutiori ,standard rdeviations for IQ do indicate an improvement ,in within-cluster homog~neity on IQ.The homogeneity requirement is empirically the 'best in the 5-clustersolution. Each of the groups (clusters) contains a diversity of caiElg()rical diagnoSEls(Fig>l). Children clinically dio agnosed as autistic,atypicaLa~d mentally retarded are representedin~achof;the functionally homogeneous groups. Group. 2 c<;>ntains cllildreilclinically diagosed . FIG. 1; Diagnoses represented in clusterS. as autistic and atypical only. Allotllergroups contain enty~five percent (N ~6) of,children with known children who have been clinically diagnosed autistic, ,'. .retard~tionsyndromes (e.g.,,: Down's, Cornelia de atypical and mentally retarded. ';., .. Table 3 presents the cluster "centers"otthe means, . Lange) are in grouP3.,; . _ ."whichcan be used to clinicallymterpretthe functional As Tabl~3' indicates, this group of children in patterns characteristic of each group. cluster 5 shows high levels of symptomatology and . Clusters land2 show.the following Junctional pat- . severity similar to group 2, but have IQs that are terns: .big-l"er 'levels .ofbehaviorjil symptomatology, lowest of the 5 clusters. This then is the most severely . ..•.seveiity and intelligence; /. . .impaired of the g r o u p s , ' . ··Thesecondset of clusters, 3: and 4;havethefollow-'... A summary of thefunctionalpatternsofthechilihg .£uncti6naipatterns:·"relatively low levels of abnor-' dren in eachduster may'be found in:Figure 2; . malbehavioral symptomatology, globally less severity Given tbefunctional homogeneity of the 5-cluster ;:tJia,n -dusters 1 and 2withIQ ,scores for cluster 3 solution, the attempt to'establish the validity of play "W~;30),10wer than cluster 1 and 2, with cluster 4 aJ;ldJanguage behavior as'potentially useful indicators '" showing lowest levels of impairrpent of the 5 clusters _.of developmental differences seems enhanced: " .oIl'alldimensions withIQapproachingcluster 1. SevTable 4presents'univa.:datedata on the play and

516

SHERMAN ET AL. TABLE 3

Means of the Classifying Variables for the 5-Cluster Solution· Cluster Measure BCDP-Total Global Severity IQ ·Three univariate analyses of variance were performed on the three classifying variables; each was statistically significant at p ~ 0.001. BCDP = Behavior Checklist for Disordered Preschoolers.

635

36-50

TABLE 4

Clusters

Scoring Total Symptom Score

1

2

3

4

5

Medium

High

Low

Low

High

SCOP

>50

Means of the Play and Language Measures by Gr()up· Group Measure

~GIObal

Severity Rating Score

1-2.9

3-4.9

5-6

lQ

650

51-70

>70

Medium

High

Medium

Low

High

High

Medium

Low

High

Low

FIG, 2. Functional patterns of subjects in the five clusters. BCDP = Behavioral Checklist for Disordered Preschoolers (Appendix I).

language measures by group. (Multiple comparison .procedures for detecting pairwise, statistically significant differences among the 5 groups are considered in a multivariateratherthan a univariate context. The reasons for this approach are subsequently outlined in the paper.) As the data indicate (see Table 4), each variable is significantly related to group membership. More specifically, symbolic ability is most impaired in groups 2 and 5, less impaired in groups 1 and 3, and least impaired in group 4. Also, these patterns "transfer" to language behavior. Groups 3 and 4 show higher levels of language development than do groups 1,2 and 50n the language measures. The importance of IQ is compellingly demonstrated by the 5th group's play and language behavior. Over the' entire set of play and language measures, this group of children almost uniformly functions more poorly than even group 2 to whom they seem so similar on play measures except for IQ. In addition toa univariate. approach to comparing the various groups of disordered children on various aspects of play and language behavior, a multivariate approach, multivariate analysis of variance, was also examined. This technique tests for statistically.significant differences among means, as does univariate analysis of variance. However, the effect or association of the independent (or grouping) variable is estimated in terms oftwo or more dependent variables (Winer, 1971). The advantages of this approach are 2-fold. First, it provides a test of the relationship of the set of five play and language measures, taken as a set, tp the grouping variable. Second, the simultaneous approach is especially valuable in this application be-

1 Play Scale Objects Symbolic Diversity Peers

2

3

4

3.61 2.20 2.44 3.56

2.68 1.20 1.80 2.80

3.84 2.47 3.20 5.00

4.55 3.29 3.40 5.33

24.67

24.00

30.00

40.27

5 1.61 1.00 1.89 2.44

Grand Mean 3.48 2.27 2.73 4.13

Language Language Comprehension Rating

9.78 . 27.79

·Six univariate analyses of variance were performed on the four play and one language measure; all were statistically significant at p ~ 0.001.

cause our play and language measures are correlated. As such, the sequential or separate univarite analysis of variance, which does not adjust for correlatioml' among these variables, may suggest significant findings which are the result of redundancies in the data or capitalizations on chance. For these reasons, then, a multivariate approach is to be preferred. A chi square statistic (a multivari~te F ratio analog), for the test of the association between the group membership variable and the set of five play and language measures is statistically significant (p < 0.001). Wilks lambda (A) is a general statistic which can be used to quantify differences among the groups with regard to their respective mean vectors on the play and language variables. The statistic is an inverse measure of the association between the set of play and . ' language variables and the grouping variable. The smaller its value, which ranges from 0 to 1, the greater the differences among the five clusters of children on the play and language measures. In this application, Wilks A statistic is 0.189. In other words, not only are . the group differences statistically significant, but more important, the differences are also sizeable. This finding implies, then, that there is a substantial correlation between the functional' and play measures which' is preliminary evidence for the validity of both sets of measures. Given evidence ofsignificant differences ·amongthe

517

PLAY AND LANGUAGE

groups, two further questions must be addressed. First, on which variable(s) do the groups differ? Second, which groups diffedrom each other? The first of these questions was answered '. via multiple discriminant analysis, the second by combining the results of the discriminant analysis with multiple comparison procedures. . ,Discriminant analysis is an analog· to regression .analysis except that it analyzes a qualitative, rather than a quantitative; dependent variable (Cooley and Lohnes, 1971). In this application, the play and lang9age.measures are used as predictors, or discriminators,. of group membership as derived through the cluster analysis. In discriminant· analysis'each of the predictors re-' ceives a weight proportional 'tQ its strength in predicting or differentiating the five functional groups. In·verting the.·analysis'somewhat,-the weight (standard;.. · · . ized discriminant function coefficient) of each predic.. tor is proportional to the size ofthe differences across . the five groups in the'means of t.hat play or language variable when it has been adjusted for its correlations with the remaining three variables. Taken together, the set of four predictors,' when multiplied by their respective weights, define anew composite which maximallydiscriminates the five groups in terms Of the four components;. This composite is called a "discriminant function," The mean score of each of the five groups on the discriminant function is called its "centroid." The mean ofthe fupctionitself is zero. As a means of addressing,the first question posed, the discriminant function coeffi<::ients (standardized) may be compared to evaluate.therelative contribution . of each play an the continuum which maxi, mally differentiates the groups. Thus, the continuum is primarily defimid in 4:lrms of separating the groups .according to their peer- play relationships, object use ajld language .comprehension: A lesser contribution is made by the diversity variable; The symbolic (pretend) . variable makes no unique contribution to group differentiation. The negative signof the diversity ·variable, certainly "anomalous given thesigIls of the other play measures, is most likely a function: of its very strongcorrelatio~ with peers variable. This correlation, r =0.74, is not 'only the strongest· bivariate association among the discriminant variables, but it is well above the next strongest such association (r;= 0.57). This pattern of asso¢iation is suggestive of a "the problem of multi-

collinearity." Multicollinearity refers to a number of ' related statistical problems one of which seems particularly relevant here. In the presence of variables which are highly correlated the discriminant function coefficients .of those variables typically become highly unstable, often reversing algebraic sign (Cohen and Cohen, 1975; Green, 1978), and thereby producing seemingly paradoxical estimates. In the present circumstance, it would appear that the peers variable is "coopting" part of the discriminatory power of the diversity measure. In order to test this speculation and;if confirmed,to mitigate its effect in the results, a stepwise discriminant analysis was performed. The results of this analysis (See Table 6) are quite consistent with the initial results (see Table 5). As expected, the redundancy-in the battery of play measureshasbeeneliminated by the exclusion of the diversity and symbolic variables in thel'!te.pwise solu-' tion. A demonstration· of this redundancy is evident in the lack of any meaningful loss of group separation as indicated by the groqp centroids of Tables 5 and 6. Finally, and perhaps most centrally, the revised discriminant analysis suggests· that language is more important than play in differentiating these groups of developmentally disordered children. In rough quanTABLE 5 Discriminant Analysis Assessment of the Relationship between Play and Language Behavior and the Grouping Variable

Discriminant Function Coefficients

Measure

Objects· Symbolic· Diversity" Peers·

0.43 -0.01 -0.16 0.40

Language Comprehension

Centroids

1.74

0.55 -0.30 -0.94 -2.68

Group

4 3 1 2 5

0.63

·Reversed scoring: high score implies less impairnient.

TABLE 6 Stepwise Discriminant Analysis Results of Play and Language Behavior and the Grouping Variable

Measure

Discriminant Function

COeffi-

Centroids

Group

cients Objects· Peers· Language Comprehension

0.41 0.29 ,.0.62

1.73

0.55 -0.30 -0.99 -2.65

·Reversed scoring: high score implies iess impairment.

4 3 1

2 5

518

SHERMAN ET AL.

·titative terms, we would say that "language,"on .average," approximately 75% more·' di&criminating. than "play" variables in differeritiatingJevels of functioning . within this sample of disordered. children. As interesting as it is to .know which measures discriminate among groups of developmentallydisordered< children, it is also of interest to know which groups can be reliably discriminated in terms of play and language performance. Obviously, for. these performance· measures to be dia.gnostically or, perhaps, prognosticallyuseful, it is important to know how "fine" or "sensitive" are the discriminations which can be made using play and language variables. It would speak well of these measures if they could differentiate levels of functioning among the groups. Table 7 presents some data .on these issues. Within the· body of the table,F statistics and their associated sigriificance tests are presented for the. pairwise comparisons among thee centroids, or "multivariate means," ofthe play andlanguage .measures as reflected in' the discriminant function. In effect, each group is compared to every other group. Those pairs of groups which. are significantly different can be saidto be discriminable by means of play and languag~ performance. Interestingly, only one group comparison fails to reach statistical significance. This comparison .involves groups 1 and 2, These data strongly suggestthe play and language measures can be of considerable value in. validating clinical judgment of functional status iIi some cases and helping to inform those judgments in others~ Discussion It is possible clinically to identify and to categorize subgroups of developmentally disordered children whose behavioral manifestations cluster together. to form specific syndromes, such as early infantile autism, mental retardation, atypical pervasive developmental disorder.· Yet, categorizing an individual child is often extremely difficult because he or she may manifest a partial syndrome or a mixture of behaviors from more than one syndrome. TABLE 7 Pairwise F-Ratiosand Assocl.ated Statistical Significance Tests Group Group 1 2

2

3

4

1.35 (p

= 0.27)

(p

= 0.03)

(p

= 0.00)

(p

= 0.00)

3.26

3 4

8.97

5

9.75

3.93

(p

= 0.01) 9.27

(p=O.OO)

3.25 (p

= 0.03)

(p

= 0.00)

3.62 (p= 0.02)

15.52

34.40 (p

= 0.00)

Because of these problems,. investigators have proposed· systems of classification that are.· in .closer accord with our state of knowledge about the functional significance of symptomclul!lters and their severity. For example, Wing and Gould (1979) have proposed a system ofdassification for disorderedschool~age children that is based primarily on a single dimension, the quality of social interaction. Their rationale rests on the well-known· fact that a child's social functional status correlates positively' with, prognosis, irrespec~ tive of diagnosis. This is so if the disorder described is not progressive, such asa brain.tumor or demyelf+. nating disease. These conditions would clearly· show progression, arid therefore categoric~l diagnosisisimportant. Neurologists tend to .include .• autism among the static encephalopathies to indicate thenonprogressive relationship to)brain fuJ1ction. However, in the absence of discriminating etiologic or genetic factorsin these disorders"perhapsa functional dimensional approach. to· diagnosis is·' indicated. Categorical diagnosis may be premature and even nonheuristiccin thatitdirects..u s to distinctionsthat have little bearing on outcome, capacity for therapies,or research into etiology. StudyingonlyKanner~s sYlldromeor some other subgroup has lead to conclusions that are of very limitedgeneralizability for Iarger groups of chil~ dren with several impairmentsassociatedwi.th social . deviance. Therefore, we haveintroduced a system: of classification based on· functional status that derives from dimen~ions that are relevant to life adaptation. We find a continuum of disordered function that cuts across diagnostic categories"'and ,may allow more meaningful···· comparison and· correla.tion between groups than does current diagnosis; Each of the functionally homogeneous ,groupings'.cbntainsamixture of currently defined. clinical· diagnostic categories.. The three measures (i.e, IQ, total behavior score, .global severity) used to derive the functionally homogeneous groups are identical to those measures previously decribed by Rutter (1971.) and othel's as having prognostic significance withinthe narrowly defined group of early infantile autism. TheyhaYtl been closenasglobal indicators of functional and.adaptational status.Follow-up study will enable predictions tobe madecon~ cerning outcome for each of then~wly derived group~ ings. We have als()presentedindica.t()r~ of play functioning that reflect varied clinicallY important aspects of play rather than positing tnat'playconsists only' of a series of Piagetian cognitive steps. The absence of symbolic (pretend) play has been described by Kanner (1943,1973) as being a central clinicaUeature of early infantile' autism but it appears nowhere in DSM~III asa criterion for diagnosis;Other investigators (Wing

519

PLAY AND LANGUAGE

eta1., 1977) have demonstrated that the presence of this symbolic impairment in 5":"14-year-old children cuts across diagnostic categories. We have confirmed this to be true jnpreschool sub]ectsand have shown th.at, whil~ th.ere is some association between one symbol systeIn(symbolic or pretend play) and another symbol system (language developxnent), these two systems are notidentical: level of COIrtpetence in onewas not stronglY~correlatedwith.. competence in the -other in our group of disordered preschoolers. (The pooled within groups correlation is 0.25.) In combination with linguistic competence, "peer play level" allows us to discriminate best among the functionally.' homogeneous ·groups that have been derived. Such a finding gives One pause and forces us to reconsider if we 'are too ensconced in a traditional vision of language andplay as solely cognitive achieve~ merits and have ignored the obvious fact that both evolve developmentally in a social field. Traditionally too, we are accustomed to considering cognition asa correlate .of brain function; clearly the capacity for social interaction. is .equally biological. This fact should perhaps redirect our classifying efforts to include functionally. critical. dimensions. Autism and certain. forms. of retardation have been' described as similar .. in some ways because they share a soci.alsymbol problem in development (Wing et aI., 1977). We should not segregate these', children into categoriesbecause they do or do not share other features of an establisheddiagnosticscheme. Rather, we should consider the potential clinical benefit of an approach that employs mnctionaldimensions. This would then direct our rehabilitative efforts to bolstering function, regardless of'diagnosjs, until etiology is better understood. It also will aid inhelpirig parents to see more clearly past the frightening labelsthat we use for their children.

Summary The first part of this study tests the validity of diagnostic labels for neuropsychiatric disorders in preschool children by applying a statistical cluster analysis to data .derived from IQ scores and' behavioral ratings. Results i:n'dicate that diagnostic similarity does not always accord with functional similarity since arange of diagnoses are found in each'of the statistically derived clusters. . The second part·· of this study tests the usefulness of several measures of pla.yand language behavior in discriminating among the clusters derived in the first analysis. We have found that in .combination with .linguistic competence, "peer play level" discriminates best among the functionally homogeneous groups that have been derived. We conclude that classification based on functional

status may be more relevant to clinical practice, research, educational planning and prognosis than are diagnostic labels.

Appendix I BEHAVIOR .CHECKLIST FOR DISORDERED PRESCHOOLERS' (BCDP)

1. Indifference. to, denies. or .ignores existence of people (indrawn, self~absorbed; withdrawn, "dreamy"):

o.

always reacts appropriately

...

1. frequently interrelated but has o~casional periods of

unawareness 2. occasionally interrelated and interacts hut predominantly indifferent' 3. nO interest or interaction 2. Eyecontact: O. alway~ appropriately establishes .eye contact i. frequently estltblishes eye contact but occasional absence or aversion 2. occasionally niak~s eye contact 3; never engages in eye contact 3: Response to active attempts at engagement by other people: O. always acknowledges reasonable attempts 1. frequentlyacknowledges.attempts 2. occasionally acknowledges attempts 3. never acknowledges attempts 4. Physical contact (appropriate categories from both (a) and (b) may be indicated): . Aversion

Clinginess

reasonable accept(b) O. reasonable seekance of physical coning out.of contact tact 1. frequently accepts' 1. occasionally clings physical contact 2. occasionally accepts 2. frequently clings physical contact 3. never seeks or ac3. constantly seeks contact-clingy, cepts physical con" melting tact-is aV!lrsive to contact 5. Uses unusual, bizarre orsterotyped forms of relating to people (e.g.,.sniffing, .kissing, using. people a~ an extension of self as though they we.re tools: distinguish from merely underreaction Or overreaction): . O. never .. 1. occasionally 2. frequently 3. always 6. Excessive aggressive behavior, i.e., hitting'kicking, throwing things at someone or something, biting: O. never . 1. occasionally 2. frequently 3. always 7. Negativistic behavior-equal. and oppbsite dii'ectedbehavior to be distinguished from withdrawal. Says or . indicates "no": (a) O.

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SHERMAN ET AL.

o.

never

1. uses materials representationally, but play lacks a

1. occasionally

2. 'frequently 3. always 8. Interactive play: o. age appropriate: some group play begins to occur in addition to parallel play; includes interaction among participants and taking turns 1. predomi,nantly parallel play-plays along side rather than with another child, often erigagesin same activity by acts quite separately , 2. attempts atparallel or interactive play but predominantly isolated 3. exclusively isolated play-type activities or no play 9. Attitude toward presented objects: o. 'appropriate acknowledgment and attitude toward presented objects (toys,games) with no noticeable over or underreaction (appropriate categories from , both (a) and (b) may be indicated if there are shifts between overreaction and underreaction)

Overreaction (a) 1. slight uneasiness at

,

presentation but adapts after brief time

Underreaction (b) 1. slight interest and

awareness but not sustained (picks up and quickly puts down) 2. awareness but no real interest (i.e., looks but does not explore) 3. complete indifference to presented objects

2. moderate overreaction at initial presentation but eventually adapts 3. intense overreaction (anxiety aversion, excitement, pouncing or grabbing) 10. Unusual responses to objects or body parts of self or others (e.g., smelling, stroking, mouthing, tapping): o. never 1. occasionally 2. frequently 3. always 11. Distractability-ease of diversion of attention: o. attends to task or pursuit (interruptions and shifts infrequeP,t and understandable from context) 1. OCcasional and unexplained shifts of attention ,2. frequent shifts-approximately haif the observation time spent in shift,ing attention 3. constant moment to moment shifts in attention 12. Perseveration-tendencyto continue with on-going activity even when it becomes inappropriate or,unnecessary:

O. never 1. occasionally 2. frequently 3. always 13. Type of play activity: O. creates imaginative, dramatic play with a recognizable theme, e.g."make~believe uses of materials of situations (','I'm King. Kong"), creates imagi.native products with raw materials, e.g., sand, clay.

sustained theme, e.g., moves block back and forth as truck, treats doll like baby 2. occasional activity recognizable as play but repetitive and stereotyped 3. no imitative, imaginative,. dramatic or' representational play 14. Attitude toward objects that are either harmful or dangerous: O. proper respect for dangerous objects,no apparent intentional involvement in dangerous acts 1. occasional unawareness of, or involvement with dangerous objects 2. frequent indifference to, lack of acknowledgment of, or involvement with potentially dangerous objects or situations 3. repeated indifference to potentially harmful objects or repeated engagement in dangerous acts (include here mouthing objects indiscriminately, climbing iit precarious places) 15. Disordered motility and activity level '(appropriate categories from both (it.) and (b) may be indicated if there are shifts between' hyperactivity and, hypoactivity: o. average motor activity when sitting and standing

Hyperactive

Hypoactive

(a) 1. some excesSive motor

(b) 1. mildly dimin-

activity (occasional darting, wriggling, rocking or fidgeting but is able to sit or stand still) 2. sits or stands still at times but mostly excessive motor activity

ished restlessness and energy level

2. moderately diminished restlessness and energy level 3. exceptional ab3. cannot sit or stand sence ofchi1still, "perpetual modish restlesstion"-excessive, unness-lack of predictable irrelevant apparent enmotor activity ergy 16. Involuntary movements (tremor, tics, chorea, dystonia): o. never 1. occasionally 2. frequently 3. always 17. Postural oddities and motor sterotypies (whirling,posturing, rocking, toe-walking, hand-slapping, twirling object): o. never 1. occasionally '2; frequently 3. always 18. Fine motor coordinations: O. smooth steady, precise fine motor movements (as manifested by pencil grasp, steadiness in block building, ease of manipulation of objects) 1. slightly awkward and clumsy 2. moderately awkward and clumsy

521

PLAY AND LANGUAGE

3. extremely awkward and clumsy-,manipulates objects with great difficulty and imprecision 19. Gross motor coordination: , O. well coordinated; smooth; graceful gross motor movement 1. slightly awkward and clumsy 2. moderately awkward and clumsy 3. extremely' uncoordinated-poorly controlled and modulated gross motor movement Muscle Tone: Check, if child looks excessively floppy or doughy ( ).

20. Lack of variety and' depth of affect .(impassiv~" dull, flattened, blank expression): ' . O. appropriate variety and depth 1. slightly limited ' 2. moderately limited 3. extremely limited Note: If item 20 is rated "3,"do not rate items 21 and 22.

21. Poorly modulated affect: 'rapid shifts of affect, lability, excessive overreaction, explosiveness, escalation of affective expression: O. well modulated-no extreme or unexplained shifts 1. occasional poor control-'-poorly modulated 2. frequently poor controlled--:--poorly modulated 3. always poorly controlled---:-poorly modulated 22. Fearful, apprehensive, overconcerned: O. never 1. occasionally 2. frequently 3. always Inappropriate Affect: Check, ifaffect is grossly inappropriate or silly ( ).

23. Percentage of vocalizations recognizable as words (jargon, babbling, screaming counted as vocalizations but not as words even if interpretable,e.g., .child screams when hit. Words need not be context appropriate, e.g., if a child says "elephant" fonio'apparent reason, this is counted as a recognizable word. Count such phrases as "thank you," "goodbye," "bye bye" as one word; all contractions, such as "can't," "isn't,"etc~aret() be counted as two words): Estimate O. nearly all vocalizations recognizable as words 1. more'than 50% recognizable aswords 2. less than 50% recognizable as words 3. almost no re~ogi1izable speech Note: If item'23 is rated "3," do not rateitems 24 through 29.

24. Vocabulary size (number of ,different recognizable words-'-noted only during period()f observation, e.g., if child said "doggy" four times aild"thank you" twice, vocabulary consists of two words): O. 50+ different words 1. 21-50 different words

2.6-20 different words 3. less than 6 different words 25. Average sentence length (contractions, e.g., "I'm," 'words; phrases such as "thank "There's" count as you" count as one. w.ord,;repetitions .are t() be counted only once in a sentenc;:e, e.g.; "look: .. look at the truck," as a four-word senieri'ce): ' O. on the average,4-word sentences or: more 1. on the average, 3"wordsenterices 2. on the average;' 2~vJordsentences 3. almost entirely single words 26. Prollo\ln usage (use()f first, sec()ndperson singular): O~ first and/or second person employed in speech and ".' " ,'. ',,' when used"userl correctly 1. first and/or sec()nd person~mployed with noreversals bu¥ with some othe~ mistakes (e.g.; "me dolt" for "I do, it," "niines" for "mine,") , " 2. .first and/or secolld person employed but reversals ,rioted," e.g.~ calls~elf"you" and/or other(s) by first ,, pers?n, " . > ' 3. no use of first or secondp~rson '

'two

Comments: Note ifchildused she, he for self and/or a person addressed directly.:.....that is, When "you" appropriate. Note if only first or second person used.

27. Immediate echolalia. (Immediate a~d exact repetition of a word or sentence child has hell;rd another person say.) Count as an echo if child, e~g.; hears "see that" and says "see that ... see that,"j.e., If repeats exactly more than once. Do notcotInt if child changes utterance, "see that, ... see that there." Do ll()t count ifperson directly attempts to get repetition, e.g., Adult: "See? A cat. Can you say that?" Child: "A cat.".: O. never 1. occasionally 2. frequently 3. always 28. Mechanical speech (mechanical, flat, unmodulated, or s1;e~eotyped speech; child speaks as iffrom rote memory. Apply only to recognizable words, sentences, not 'to jargon or babbling orwhining). This can occur in echoic speech as well as in spontaneous speech: O. no mechanical speech 1. most speech not mechanical (normal intonational pattern inmost speech) 2. some speech. not mechanical (normal intonational pattern in some speech) , 3. all or almost all speech mechanical 29. Context-appropriate, ,formed (reCognizable), speech (context refers to physical, setting, child's or other's activities or state, or prior utterance. "Appropriate" means that it makess~nse to· you following normal conversational rules. This refers to realwords which are 'used out. of context, i~releyant or partially relevant to , , context. Do not rate Jargon):', " O. l:\lways appropriate t() conte# L pr~dominantlycQntext appropriate (about 75% speech context app~opriate) 2, miJl:ture o(p
522

SHERMAN ET AL.

3. predominantly context inappropriatet,a(about 75% speech context inappropriate).

and/or clinging. Grossly disordered motility patterns with stereotypic movements may be seen.

Appendix II

Appendix III

GLOBAL. SEVERITY RATING

PRESCHOOL LANGUAGE COMPREHENSION MEASURE

Mild Moderate Severe Rate from 1 to 6: 1 2 3 4 5 6 Select the category and scale number that best describes the child's overall level of functioning based on your clinical impression.

Check each item passed. Examination may be carried out naturalistically with questions in· mind before. Circle questions not asked.

1, 2 Mild: Children whose behavior is marked by slight impairment of functioning in all areas, fluctuations from mild to moderate in several areas, or with an isolated area ofdistllrbance in a generally adequate developmental profile. Child is usually related and in good contact but occasionally may 'appear unaware, "out of it" or aversive to social engagement. Stereotypic or unusual forms of relating to people rarely occur. Ability to tolerate frustration and delay may be impaired only in speci,fic settings with episodes of aggressivity or withdrawal usually shortlived and/or amenable to intervention. Play shows movement toward imagination, creativity and attempts to involve others. Activity level may be marked by occasional excessive motor activity or excessive lethargy but child is usually able to sit or stand still. Fine and gross motor coordination is generally adequate or only slightlyawkward. Language. is predominantly intelligible and context oriented with formed sentences. Comprehension is age appropriate. 3, 4 Moderate: Children whose behavior is characterized by a significant degree of unintegrated activity. There 'may be moderately disturbed functioning in all areas with fluctuations from mild to severe, or about equally scattered areas of poor and better functioning. General impression is one of very uneven developmental skills and lability. Social relationships may be marked by shifts from periods of indifference to involvement. Moderate or intermittent hyperactivity, irritability or apathy may appear. Some capacity for tolerating frustration and anxiety is present so that contact is not completely avoided, however, stereotypic ritualized motor and social mannerisms are also present. Some speech is recognizable as words possibly with formation of 2-3-word sentences. There may be a mixture of context appropriate and inappropriate speech and mechanical and normal intonational patterns. Comprehension is clearly present for simple commands though responsiveness may be variable. 5,6 Severe: Children whose behavior is permeated by grossly stereotyped erratic and/or deviant functioning in all areas. Severe hyper- and hypoactivity and/or extreme anxiety with low frustration tolerance and lability or blunting of affect may be present. Responses often occur with no external provocation. Little or no speech or gestural communications; vocalizations if present are characterized by unintelligiblity, incoherence or echolalia. Socially isolated; makes few or no attempts at interpersonal contact; generally unable to tolerate approaches by others. Adaptive behavior may be characterized by negativism,aggressivity,

1. Responds to calling: (with gesture;

2.

3.

4.

5.

6.

7.

8.

9. 10.

without gesture) (comes toward caller; smiles responsively; looks up) 1 Responds to calling name without gesture: (i.e., seems to recognize name) (Rate "+" if response occurs twice; if a 2 response to a general call rate "-") Looks attentively (18 months): While looking at a picture book or toy array: Show me the block, dog, ball, etc. (Rate "+" if points to one) 3 Responds to single direction (18 months): Pick up the block Give the block Show the block (Rate "+" if acts or negative action reveals (s)he understands) 4 Recognizes parts ofwhole (18 months): Discriminates parts of an object (toy car; house) Show the wheel Show the window Show the door (Rate"+" if 2 correct) 5 Understands functions or predicted actions (May do. them spontaneously without query as part of naming):, e.g., What do we do with a comb? Where does a boat go? What does a dog say? (Rate "+" if 2 correct) 6 Shifting name of subject (pronomial or nominal deixis): e.g., Comb (subject's name) hair Comb (examiner's name) hair Comb the dolly's hair Comb (your, his, my) hair 7 (Rate "+" if 2 correct) Two stage requests: Pick up the block and put it on the table Pick up the car and roll it to me (Rate "+" if 1 correct) 8 Body part designation: Show me dolly's eye, ear, nose, mouth, hair (Rate "+" if 2 correct) 9 Distinguishes others (2 stage): Pick up the blocks and give one to mother and one to me 10

_

_

_

_

_

_

_

_ _ _

523

PL2\Y AND LANGUAGE

11. Understand prepositions: e.g., Put the block on the table Put the block under the chair In the back of the chair In front of the chair .'(Rate-·"'+" i(2correct) 11 ~ 12. Understands color: Show me the red block, yellow block, green block, blue block 12 _ (Rate "+" if 2 correct) 13. Understands numbers: Count the blocks-register highest level (s)he counts to Give me 3 blocks 13 _ (Do not score "+"ifrote counting) 14. Can shift predicate on same object: (Allow one preseveration in prior set to rate "+") Count the blocks Show me the 'red block 14 _ _..,.-_ Make a house with blocks Basal _ _--' High _ Record highest item passed Recordbasallevel (last item below which no item was failed) e.g., child"passes 1-5; misses 6 and 7; passes 8; fails 9-14.

Appendix IV PLAY ITEMS FOR DISORDERED PRE-SCHOOLERS

Developmental Line: Objects

Inspection (visual tactile)

~

Form recognition ~ Groups ~ Sequences

1. Visual and tactile inspection of objects. Mouthing or

chewing objects. Nondiscrimimlte motor activity (shaking, banging) 2. Objects used in accord with form. Aware of functional or sociocultural use (e.g., comb for hair, rolls car) 3. Groups-demonstrates understanding of physical and/or functional similarities of objects 3.L Homogeneous groups-(e.g., chairs with chairs, blocks with blocks) 3.2. Categorical groups~(e.g., chairs with tables, dishes with utensils) " 4. Sequential acts-performs two consecutive parallel acts-(e.g., washes doll, then car; gives cup of juice to self, and others) " 5. Further elaborates on a sequence, (e.g., washes doll then drys doll, puts doll in bed, rocks bed) Developmental Line: Symbolic Imitates an act (immediate; delayed)

-+ .Symbolic

(pretend) activity (iconic; A stands for

B) L Imitates an act LL Immediate imitation L2. Delayedimitation

-+

Elaboration of symbolic activity into a "theme"

-+

Further elaboration + conscious awareness of pretend

2. Symbolic (Pretend) Acts-e.g., eating, drinking, pouring (presumably imaginary substance) pours from one container to another (iconic) 3. Elaboration of pretend activity into a "theIne," e.g., while eating or drinking imaginary substances, elaborates into a "tea party" 4. Symbolic (Pretend) Acts (the use of one thing to represent another, e.g.; a stick used as a train, a block as an airplane (A stands for B) 5. Elaboration of pretend activity that includes non-visible stimuli, e.g., people, objects, situations, Ulles self as a "pretend. object in role playing, e.g., pretending to be a lion DEIDelopmental Line: Diversity

Limited, repetitive interests

~

Diverse, flexible "interests

L Interest pattern consists entirely of repetitive stereotyped pursuits except when child is directed by an adult 2. Interest pattern consists primarily of repetitive stereotyped pursuits 3. Interest pattern is partly rigid or repetitive and partly constructive, even without supervision (child may clear the table and wash dishes on his own but then choose to return to listening to the same record played over and over again) 4. Interest pattern is diverse and varied, devoid of stereotyped repetitive pursuits Developmental Line: Peers

Isolated activity

~

Reciprocal interactive activity

~

Symbolic reciprocal activity

L Isolated activity: No sign of awareness of activity of others unless they intrude. Plays; fantasies or manipulates self or objects alone 2. Shows awareness of activity of other children (looks or touches but not further engagement) 3. Mirrors or imitates another child's actions or activity 4. Engages in parallel activity with child (does same thing with·two different objects) 5. Engages in activity with another child with same object or toy as the focus 6. Reciprocal-interactive activity (e.g., rolls car or throws ball back and forth; takes complementary role, etc.) 7. Symbolic-reciprocal activity (changes or shifts roles with a peer)

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