COPYING ABILITY OF PRESCHOOL CHILDREN WITH DELAYED LANGUAGE DEVELOPMENT

Vanessa Moore James Law

Preschool children referred for psycho- logical assessment because of delayed language development often appear to have difficulty with copying tasks, even rudimentary ones. Apart from a case study of an exceptional autistic child by Selfe (1977), a search of the literature failed to reveal any studies directly examining the relationship between language development and drawing ability of preschool children, although one study did note in passing that two-year-olds who were poor communicators drew far less than their peers who were good communicators (Starte 1975).

Copying tasks are used in the non- verbal sections of several developmental scales and intelligence tests commonly used to assess preschool children, in- cluding the Griffiths Mental Development Scales (Gsiffiths 1954, 1970), the Wechsler Preschool and Primary Scale of Intelligence (Wechsler 1967), the McCarthy Scales of Children's Abilities (McCarthy 1972) and the British Ability Scales (Elliott el al. 1978). Follow-up studies of children whose language development appears to be delayed at age three have found that some still have below-average non-verbal skills up to the age of 1 1 years (Fundudis el a/. 1979, Richman er a/. 1982, Stevenson 1984, Silva el a/. 1987). It is important to establish, therefore, whether difficulties with non-verbal skills

are already apparent in this group at a preschool age, since clinical and edu- cational psychologists assume that non- verbal performance can be used to distinguish young children with specific language delay from those with general developmental delay. In general, children with language delay are expected to per- form within normal limits on non-verbal tasks (Yule 1987). However, non-verbal scales contain a variety of items, not all of which may be equally difficult for the language-delayed child. It is necessary, therefore, to identify the relationship between language development and performance on these non-verbal tasks in order to establish which are the most (and least) useful diagnostically. In the present study, the copying abilities of language- delayed children were compared with their performance on two other non- verbal tasks.

Several empirical studies have focused on the relationship between language development and other aspects of cog nit ive functioning. These proliferated during the 1970s and 1980s as part of the debate about the r61e of cognition in children's acquisition of language (for reviews see Rice 1983, Siege1 el al. 1985). The Piagetian position has been influential, and several studies have been conceived within this framework, on the assumption that certain cognitive understandings, 249

such as evidence of symbolic play and object permanence, are a prerequisite for the emergence of language. However, studies of language-impaired children have produced mixed results: some have found no strong link between per- formance on non-verbal tasks and the emergence of language (e.g. Folger and Leonard 1978), while others have found that language-impaired children perform more poorly in certain areas than their peers without language impairment, for example on tasks requiring the capacity to form symbolic images (Morehead and Ingram 1973, Kamhi 1981). A number of studies have tried to define the type of deficits in cognitive processing that co- exist with language impairment, primarily in the areas of memory, rate of auditory processing, sequencing ability and hier- archical planning ability (for reviews see Benton 1978, Cromer 1987). Theoretically, therefore, a study of the relationship between language development and copying ability should provide further information relevant to the cognition/ language debate.

Finally, testing a sufficiently large number of young children also provides data on their ability to complete particular drawings at particular ages. The present study used some of the simple copying elicited in the second and third years on the Eye and Hand Co-ordination scale of the Griffiths Mental Development Scales. However, these scales were standardised in the 1950s (infant scale) and 1960s (extension scale), and only recently have attempts been made to evaluate the per- formance of present-day children (Hanson et al. 1985, Hanson and Smith 1987). The present study should contribute to this endeavour, and also provide information on the appropriateness of this particular test in the psychological assessment of children with suspected language deficit.

This study formed part of a much wider investigation of young children's language development and its relationship to other developmental and social variables, con- ducted by a speech therapist ( J . L . , in preparation). The children studied were 2% years old, an age at which they should be able to copy simple line drawings, and by which delayed language development

250 should be readily detectable.

Method Subjects The children in the study all lived in the same Inner-London Health District, where a routine developmental check is done by health visitors at the age of 2% years. Children were referred to the study by their health visitors on the basis of their performance on a screening test of language development (Dixon eta/. 1988). This comprised 11 comprehension and nine expressive language items, and a total score of less than 10 indicated failure. Children who failed the test but who were not suspected by their health visitors of having general developmental delay were designated index (language- delayed) cases, and children who passed the test formed the control group.

There were 100 children in each group initially, but four in the index group were excluded because of their poor perform- ance on a series of developmental items and non-verbal tasks which suggested generally slow development. The final study groups therefore comprised 96 index children with a mean age of 31.74 months (SD 1.16) and 100 control children with a mean age of 32.03 months (SD 1-25).

There were 34 girls and 62 boys in the index group, and 56 girls and 44 boys in thc control group. The preponderance of boys in the group with language delay is consistent with other studies (e.g. Morley 1972, Fundudis ef al. 1979, Silva and Bradshaw 1980, Drillien and Drummond 1983).

All children in both groups had normal vision, corrected with glasses if necessary. 25 index children were referred by their health visitors for assessment of their hear- ing, of whom eight were found to have a conductive hearing-loss of > 2 5 d ~ . All the control children had normal hearing.

The children came from a variety of ethnic backgrounds (Table I). Although children in both groups were sometimes exposed to languages other than English at home, English was spoken customarily in the homes of 77 index children (80.2 per cent) and 87 control children (87 per cent).

No attempt was made to define social class according to the occupation of the head of the household, mainly because of

high rates of unemployment and of single- parent families in the London Borough in which the study was carried out. How- ever, as an indication of the educational background of the families, the age at which both parents left full-time education was recorded (Table 11). There was no significant difference between index and control families in the length of education of either fathers or mothers.

Procedure All the children were tested individually in their own homes. The parent was first asked to reply to a detailed questionnaire about the child’s language and speech, and about general development in terms of mobility, toileting, dressing and feeding skills*. The child was then assessed using selected items from the Griffiths Scales. The two items selected from the Per- formance Scale were completing a rotated three-hole formboard (2 yrs) and re- assembling a screw-barrel (2 yrs 2 mths). These were included in order to incorporate non-verbal tasks apart from the drawing items in the assessment of general level of functioning. They were administered in the standard manner, as described by Griffiths.

The items selected from the Eye and Hand Co-ordination Scale all involved copying and were those which, according to Griffiths, the child should be able to do between the ages of two and three years. They were copying a vertical stroke (2 yrs), a horizontal stroke (2 yrs 2 mths), a circle (2 yrs 10 mths) and a cross (3 yrs). The child was seated on the floor, beside the examiner, in front of a blank sheet of paper and was offered the choice of two wax crayons of different colours. The experimenter then said: ‘Can you do one like this for me?’ (scribble) and the child was encouraged to imitate. After praising the child’s attempt, the experimenter then drew in turn a vertical line, horizontal line, circle and cross for the child to copy, *A score of 1 was assigned for each of: age at walking >I6 months; age when dry by day >29 months; unable to manage stairs alone at time of study; unable to assist with undressing at time of study; unable to complete rotated formboard; unable to re-assemble screw-barrel; total score for drawing 5 10. Any child with a total score of 2 4 for this combination of items was excluded from data analysis and referred for general developmental assessment.

TABLE I Ethnic backgrounds. of index and control children

Index Control N % N %

African 17 8.8 18 9 .3

Asian 7 3.6 8 4.1 Irish and White 37 19.2 45 23.3 Other 8 4 - 1 9 4.7

Caribbean and UK Black 26 1 3 . 5 I8 9 .3

*Based on mother’s country of origin (according to classification used in London Borough of Hackney statistics). Note: one index and two control families refused to provide this information.

TABLE I1 Age of parents on leaving continuous education

Fathers Index 25 28 5 I I Control I S 26 12 14

Index 24 52 13 5 Control 23 55 I2 10

Mothers

each on a separate sheet of paper. I f the child merely scribbled or made no attempt to copy, a second try was allowed and the better of the two attempts was scored.

Each child was then administered the full Reynell Developmental Language Scales (Reynell and Huntley 1977) in the standard manner.

Scoring of drawings In order to compare our results with those of other studies examining the Griffiths scales, the scoring criteria were based on those described by Griffiths (1954, 1970). In addition, a score of 1 to 4 was given according to the accuracy of the copy (Table 111). The drawings of the index and control groups were shuffled together and scored by two independent judges.

Results General development No differences were found between the index and control children for any of the questionnaire items concerned with

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T A B L E 111 Scoring criteria for drawings

Drawing I

SCORE

2 3 4

Vertical/ No attempt; Scribble or multiple

line going in completely wrong direction

horizontal line scribble; lines (1.e. >2) going in correct direction

Circle

Cross

No attempt; Circular scribble' drawing or scribble bears no resemblance to circle

(Griffiths 1970. p. 138)

No attempt; Attempt at cross drawing or scribble bears no resemblance intersect (Griffiths 10 cross 1970:~. 139)

in which lines fail to

Line generally going in correct direction but not very well formed and direction may not be maintained throughout

Rough circle which may not be neatly closed;* child must have stopped before going into circular scribble (Griffiths 1970, p. 139) Drawing in which one line definitely crosses the other, even though orientation, relative length of lines etc. may not be adequate (Griffiths 1970, p. 140)

Well-formed stroke that stops before edge of page

Circle of good shape and neatly closed* (Griffiths 1970, p. 142)

Good cross; upright line should be approximately perpendicular and horizontal line should cross it at approximately right angles (Griffiths 1970, P. 140)

*One point deducted if d rawn within experimenter 's model.

general development*. All children in both groups could manage stairs unaided, were able to help with dressing and could feed themselves. The mean age at starting to walk was 12.17 (SD 3.29) months for the index children and 11-48 (SD 2-38) months for the control children (t = 1.68, df 193, ~ ~ 0 . 0 9 ) . The mean age for being dry by day was 24.6 (SD 5.34) months for the index group and 23.08 (SD 5.38) months for the controls (t = 1.77, df 157, p < 0 * 08).

Language On the Reynell Scales, the mean scores for comprehension and expressive language were - 1.125 (SD 0.8) and - 1.71 (SD 0.67), respectively, for the index children, and -0.07 (SD 0.48) and 0.06 (SD 0.78), respectively, for the controls. These differ- ences between the two groups were signifi- cant for both comprehension (t = - 10.9,

*All t he children had been screened by health visitors, using a developmental schedule originally used for t h e Nat ional Chi ldhood Encephalopathy Study (Bellman er a/. 1985). which covered posture and large movements, vision a n d fine movements. a n d social behaviour and play. On ly children performing at an appropriate level in all these a reas were referred for study.

df 180, p<O.OOl) and expressive language ( t= - 15-91, df 172, p<O.OOl). (These data are incomplete since some children in both groups refused to complete both scales.)

For practical purposes, a cut-off score of < - 1 is used by speech therapists to indicate possible language delay. That score was obtained by 45 per cent of the index children for both comprehension and expressive language, by 5 per cent for comprehension alone, by 37 per cent for expressive language alone, and the re- maining 13 per cent scored just above the cut-off point on both scales. There was a strong positive association between the results of the screening test and those for comprehension (r=0.70, p<O.OOl) and expressive language (r = 0.80, p<O.OOl), which supports use of the screen as a valid indicator of suspected language delay.

Performance items Significantly fewer index children were able to re-assemble the screw-barrel (xz=5.176, df 1, p<0.02) (Table IV), but there was no difference between the two groups in performance on the form- board task (x2= 1.768, df 1, p<O*18).

Copying The two independent judges assigned identical scores to 176 of the 195 vertical line drawings (90.3 per cent), to 168 horizontal line drawings (86.2 per cent), to 165 circle drawings (84.6 per cent) and to 181 cross drawings (92.8 per cent). Most differences between the judges were of only one point: differences of more than one point occurred for the drawings of one vertical line, three horizontal lines, and two crosses. It was concluded, therefore, that the scoring system was reliable, and differences between the judges were settled by consensus.

Table V shows the scores of the control children for the copying tasks. It is clear from these results that the tasks are in the correct order of difficulty, and that most normal 2 '/z -year-olds can copy vertical and horizontal lines. However, there is a marked difference in the number of children able to copy a circle (about 50 per cent) compared with a cross (20 per cent), whereas, according to Griffiths, both tasks should be achieved at about the same age.

Table VI shows the scores of the index children for the copying tasks. Significant differences were found between the distribution of scores for the index and control groups for each copy produced*: vertical line x2=32.36, df 3, pcO.001; horizontal line x2=27.66, df 3, p<O.OOl; circle 11=36-68, df 2, pc0-001; and cross x - 17.26, df 2, p<O.001.

The mean scores of the children in each group for each copy are shown in Table VII. There was a reliable difference between the scores of the two groups for each of the four copies: vertical line u=2878.5, z = -5.611, p<O.OOOI; hori- zontal line u=2882.0, Z = -5.209, p<O*OOOl; circle u=2509*5, Z = -6.031, p<O.OoOl; and cross u=3421.5, Z = -4,1345, p<O.OOOl (all two-tailed). In every case, the scores for the index group were lower than those for the control group.

As a further indication of the relation- ship between language and copying scores, Pearson product-moment correlations between scores obtained for each drawing

*For the circle and the cro\s, tcores of 3 and 4 uere combined becau5e of the m a l l number of children achieting a score of 4.

TABLE IV Number of children passing and failing performance items

Index Control

Formboard: Pass Fail Total

87 97 8 3

95 100

Screw-barrel Pass 78 94 Fail 15 5 Total 93 99

Missing observations are due 10 refusals.

TABLE V Number of control children obtaining each score on four drawing tasks

Score Drawing Vertical Horizontal

line line Circle Cross

3 6 14 55 12 34 24 62 48 18 77

12 19 3 2 Total 99 99 99 99

i ] Failure

Pass

One child refused all drawing tasks. hence total number is 99.

TABLE VI Number of index children obtaining each score on four drawing tasks

Score Drawing Vertical Horizontal

line line Circle Crosr

21 19 46 19 30 35 12

50 43 13 4 3 4 2 I :i Pass

Total 96 96 96 96

Failure 22

TABLE VII Mean scores for four drawing tasks

Drawing Index Control

Vertical line 2.36 2.99 Horizontal line 2 . 3 3 2.95 Circle I .70 2.40 Cross I .24 1.67

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TABLE VlIl Correlations between scores on Reynell scales and drawing scores

Reynell Expressive

Drawing Comprehension Language

Vertical line 0.316 0.357 Horizontal line 0.349 0.348 Circle 0.355 0.396 Cross 0.183. 0.286

'Significant at 0.02 level; all other correlations significant at 0.001 level.

and the Reynell comprehension and expressive language scores are presented in Table VIII. There is a significant positive correlation between scores for each copy and scores on both language scales.

Discussion These results confirm that preschool children with delayed language develop- ment have difficulties with copying simple figures in comparison with children of the same age whose language development is not delayed. This relationship between copying ability and language delay was found for both comprehension and expressive language. Significantly more index than control children also failed the screw-barrel task, but there was no difference in the performance of the two groups on the formboard.

The findings for the copying items and screw-barrel task are consistent with other studies showing that a proportion of pre- school children with delayed language development have below-average non- verbal and verbal skills when tested on the WISC-R (Wechsler 1974) later in childhood (Fundudis et al. 1979, Richman et al. 1982, Silva et al. 1987). Is the copying deficit found in our sample therefore attributable to general developmental delay among a substantial proportion of the index children? The questionnaire items dealing with general development were designed to eliminate any children with evident developmental delay, and no significant difference was found between the index and control groups in any of the areas covered. The formboard and screw-

254 barrel tasks were intended as non-verbal

measures apart from the copying items which would screen out children with general developmental delay, since according to Griffiths these tasks should be mastered easily by most normal 2%-year-olds. The fact that no difference was found between the two groups on the formboard supports the argument that children in the two groups did not differ in general developmental status, although admittedly the formboard is easier than some of the copying items used, so it would not be expected to discriminate well between the groups. However, comparison of performance on the form- board with performance on the copying task at the same age-levef on the Griffiths scales, i.e. copying a vertical line (2 yrs), shows that far fewer index children were able to copy a vertical line than were able to complete the three-hole formboard, whereas the great majority of control children mastered both tasks (see Tables IV and V). Similarly, copying a horizontal line was more difficult for the index children than re-assembling the screw- barrel (both placed at 2 yrs 2 mths on the Griffiths scales), while most control children again mastered both tasks (see Tables IV-VI).

These observations suggest that copying may be more difficult for language- delayed children than other types of non- verbal tasks. Furthermore, 45 per cent of our index children failed even the simplest copying task, which is a considerably higher proportion with below-average non-verbal skills (excluding copying, which does. not appear on the WISC-R) than reported in other studies-21 per cent in Fundudis ef al. (1979) and 27 per cent in Richman el al. (1982).

However, the present study is limited in the range of non-verbal skills assessed. Further research using more varied and more sensitive tasks is needed to determine the precise status of copying in relation to other non-verbal tasks. This seems important in view of the reliance placed on copying skills in preschool assessment techniques.

In attempting to explain the relation- ship between copying ability and language development, it is necessary to consider whether adverse environmental factors could have affected the performance of

the index children in both areas. Starte (1975), in his study of poorly communi- cating two-year-olds and their families, found a higher incidence of social deprivation in his index group compared with the control families. Both our groups were drawn from the same inner-city area, characterised by poor housing conditions and high unemployment, and the parents’ educational backgrounds were similar for the two groups. Thus there was no obvious evidence of adverse environ- mental factors in the index group.

Benton (1978) regards language delay, especially of receptive language, as a specific handicapping condition in itself, in that it ‘restricts the range and variety of a child’s experiences, as well as his capacity to engage in meaningful trans- actions with other people’ (p. 49). Prob- lems with verbal communication there- fore may lessen the likelihood of young children participating in other activities, such as copying and drawing, which are interactive in nature (Korzenik 1975, Moore 1984). Conversely, failure to participate in such tasks may restrict opportunities that encourage the develop- ment of language.

Research into the drawings of normal children has resulted in different expla- nations for their errors. One view empha- sises the perceptuo-motor skill aspects of drawing (e.g. Freeman 1980) and con- siders drawing errors to be primarily failures in skilled draughtmanship. Our findings suggest that the index children may have had more difficulty with fine motor skills, since a greater number failed to re-assemble the screw-barrel. However, most were able to complete both that task and the formboard, so although a disadvantage in the development of fine motor skills may have contributed to their poor copying performance in comparison with the control children, it cannot fully explain the discrepancy.

Other studies of children’s drawings SUMMARY

have stressed the symbolic nature of drawing and have considered drawing errors by school-aged children to be more or less deliberate attempts to represent aspects of the child’s knowledge of the world (Light and Maclntosh 1980; Cox 1981; Moore 1986a,b, 1987). Whether this applies to preschool children’s first marks on paper is arguable: some authors (e.g. Kellogg 1969) claim that these are merely experiments with form and are not representational, while others stress that the representational nature of drawing is understood by children from the time they first name their scribbles in the second or third year (Luquet 1927, Lowenfeld and Brittain 1970). If drawing in its simplest forms does contain symbolic elements, the present findings could be explained in terms of impaired symbolic represen- tation in general among language-delayed children (Kamhi 1981). However, these comments can only be speculative in the absence of more precise knowledge about the skills involved in copying.

Our results suggest that there is greater disparity among present-day children in drawing a circle and a cross than there was in the original standardisation of the Griffiths Mental Development Scales (Griffiths 1970). Hanson and Smith (1987) also found that a rudimentary circle was relatively easy to draw and a cross relatively difficult for their 1980 sample compared with those in Griffiths’ 1960 sample. We hope these observations will lead to appropriate revisions being made to the scale, especially since it is so widely used in clinical practice. Accepted for publication 4th April 1989.

Authors’ Appointmenrs Vanessa Moore, M.Phil., Ph.D., Research Psychologist, Institute of Child Health, Department of Neurology and Developmental Paediatrics, The Wolfson Centre, Mecklenburgh Square, London WClN 2AP. James Law, B.A.(Hons.), Dip.C.S.T., Lecturer in Child Language, The City University, London.

‘Correspondence to Jirst author.

Ninety-six 2 Y? -year-old children with delayed language development (identified by health visitors) and 100 controls were required to copy four simple items of the Griffiths Mental Development Scales, and were tested on the comprehension and expressive language scales o f the Reynell Developmental Language Scales. The index children performed worse than the controls on all four copying tasks, and poor copying performance was related to both impaired language comprehension and expression. Copying by the index children was also poorer than their performance on two other non-verbal tasks. The implications for the assessent o f children with delayed language development are considered, as well as theoretical implications with regard to the cognition/language debate.

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RESUME Capacite de copie a l’ecole maternelle en cas de retard de langage La copie de quatre simples items des Cchelles de developpement mental de Griffith fut demand6 ii 96 enfants de deux ans et demi presentant un retard de langage (diagnostique par les visiteurs de sante), qui furent egalement evalues par les echelles de comprehension et expression linguistiques des echelles de developpement de langage de Reynell. Les enfants index eurent des resultats moindres que les contrdes pour les quatre tlches de copie et la performance mediocre de copie put Stre relite aux troubles de langage (comprehension et expression). La copie des enfants index fut egalement plus mauvaise que leur performance a deux autres tlches non-verbales. L’article discute les consequences de ces donnees sur I’evaluation des enfants avec retard de langage et sur les implications thkoriques concernant le debat des relations ConnaissanceAangage.

ZUSAMMENFASSUNG Nachahmungsfahigkeir von Vorschulkindern mi( verzogerter Sprachentwicklung 96 zweieinhalbjahrige Kinder mit verzogerter Sprachentwicklung (festgestellt durch Gesundheitsberater) und 100 Kontrollen munten vier einfache Aufgaben der Griffith Mental Development Scales wiedergeben und wurden nach den Reynell Development Language Scales auf Verstandnis und expressive Sprache getestet. Die Index-Kinder schnitten bei allen vier Aufgaben schlechter ab als die Kontrollen und die schlechte Nachahmungsfahigkeit korrelierte rnit Sprachstorungen (Verstandnis und Ausdruck). Die Nathahmung war bei den Index-kindern auch schlechter als ihre Leistungen bei zwei anderen nicht verbalen Aufgaben. Es wird diskutiert, welche Folgen sich fur die Beurteilung der Kinder mit verzogerter Sprachentwicklung ergeben und welche theoretischen Folgen fur die Debatte iiber Wahrnehmung und Sprachen daraus resultieren.

RESUMEN Habilidad para copiar en niAos con retraso en el desarrollo del languaje Noventa y seis niflos de 2 aflos y medio de edad, con retraso en el desarrollo del lenguaje (identificados por visitadores sanitarios), asi como 100 controles fueron requeridos a copiar cuatro items simples de la Escalas de Desarrollo Mental de Griffith y se les pas6 10s test de Comprensi6n y Lenguaje Expresivo de las Escales de Desarrollo del Lenguaje de Reynell. Los niflos indice lo hicieron peor que 10s controles en todas 10s cuatro tipos de copias y la pobreza en las copias se relaciono con una alteracion en el lenguaje (comprensivo y expresivo). La copia de 10s niflos indice era tambien mas pobre en su realizacion en dos otras tareas no verbales. Se consideran las implicaciones de estos hallazgos en la evaluacion de niflos con retraso en el desarrollo del lenguaje, asi como las teoricas implicaciones respecto al debate cognicion/lenguaje.

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