Behavior, Language, and Development in Three-Year-Old Children'

Transcription

1 Journal of Autism and Childhood Schizophrenia, VoL 8, No. 3, 1978 Behavior, Language, and Development in Three-Year-Old Children' Jim Stevenson and Naomi Richman Department of Child Psychiatry Hospital for Sick Children, London An epidemiological study of 3-year-old children showed there to be a marked association between behavior problems and language delay. Behavior problems were present in of a random sample of 705 children, whereas of 22 children with language delay had such problems. Data obtained from a battery of developmental tests were analyzed to examine the differences between children with behavior problems, matched controls, and children with language delay. It was found that children with behavior problems scored significantly lower on these tests, particularly those concerned with language. There were no significant differences in test scores between children with language delay only and those with combined behavior problems and language delay. INTRODUCTION Various associations concerning general development, language abilities, and behavior disturbance have been investigated in children. For example, Hermelin and O'Connor (1970) have demonstrated that autistic children show specific disabilities in the processing of linguistic information. Bartak, Rutter, and Cox (1975) showed that these disabilities can be con- 'This study was supported by a grant from the Department of Health and Social Security to Prof. P. J. Graham and Dr. N. Richman. Carole Ellis was responsible for administrative assistance. Statistical assistance was given by Mr. David Boniface and programming help by Judith Pearson and Mr. Andy Hathaway. We are most grateful to Dr. James Douglas (M.R.C.) and to the Local Authority Education and Health Departments for their cooperation. Finally, we must thank the many helpful parents and children who took part in the study /78/ / Plenum Publishing Corporation

2 300 Stevenson and Richman sidered to be part of a general inability to deal with symbol manipulation. Difficulties in receptive language abilities have been identified by Friedlander, Wetstone, and McPeek (1974) in children with severe emotional disturbance. Complementary studies have been reported on children with delayed or deviant language development showing them to have a high rate of psychiatric disturbance. Rutter, Tizard, and Whitmore (1970) found that of 9 language-retarded children (with no other associated handicap) identified in an epidemiological study, 4 had a neurotic disorder. Chess and Rosenberg (1974) reported that children with language or speech delay constituted 24% of a continuous series referred to a psychiatric clinic. Of their 139 children with language delay, 99 had associated behavior problems (by far the most commonly occurring associated condition). Ingram (1959) found that 10 out of 80 children with developmental speech disorders were having psychiatric treatment, a higher proportion than in the general population. It appears that our knowledge of the association between behavior, language, and development is largely restricted to data from samples of children with handicaps. It was in order to explore these associations in a sample of children drawn from the normal population with less severe behavioral conditions that the present study was planned. This paper will report the results from an epidemiological study of 3-year-old children with behavior problems whose language and nonverbal development were individually assessed. One companion paper (Stevenson & Richman, 1976) reports the findings concerning the prevalence of language delay and general retardation and another (Richman & Stevenson, 1977) considers the social and family characteristics of children with language delay. METHOD Details of the procedures for identifying children with behavior problems and language delay are described elsewhere (Richman, Stevenson, & Graham, 1975). In summary, a 1-in-4 sample of 3-year-old children was selected from a register of all families with preschool children living in an outer London borough (Richman & Tupling, 1974). In the first stage of the survey, trained interviewers visited the families at home and gave a semistructured interview to the mothers dealing with the child's development, health, and behavior, and certain demographic factors. The interview included a Behavior Screening Questionnaire (BSQ) of known reliability and validity which was used to identify children with behavior problems (Richman & Graham, 1971). Based on the parent's account of the child's behavior, 19 items of behavior were rated as absent,

3 Behavior, Language, and Development 301 sometimes present or present to a mild degree, and occurs frequently or to a marked degree (scored 0, 1, and 2, respectively). In order to obtain a total behavior score, the scores for eight items (overactivity, poor concentration, tempers, difficult to control, unhappy mood, worries, fears, and soiling) were summed. The maximum score within each of the three following pairs of items was also added to the total score (poor appetite and food fads, dependency and attention seeking, relationship with sibs and relationship with peers), and the maximum score within the following three items was also added to the score: difficulty in settling at night, waking at night, sleeping with parents. Two further items (night and day wetting) did not contribute to the total behavior score. Thus the total behavior score had a range from 0 to 24 points. In addition, the interviewer made a global rating of the severity of the child's behavior problem on a 4-point scale: none, mild, moderate, or marked. A language-screening procedure was used to identify children with delayed language development. This comprised measures of the child's expressive vocabulary and expressive syntax. The screening tests are more fully described elsewhere (Stevenson & Richman, 1976). On the basis of these two screening procedures, three main groups were identified within the 705 indigenous families interviewed: Behavior Problem Group. Children scoring 10 or more points on the BSQ; a total of 101 children (58 boys and 43 girls), of whom 23 ( ) were from nonmanual and 78 (77.207o) from manual social class backgrounds. Control Group. Children scoring below 10 points on the BSQ; 101 children who were matched with respect to sex and social class with children in the behavior problem group. Language-Delayed Group. Twenty children identified, using the language screening procedure, as having language delay. They comprised 14 boys and 6 girls, 3 (1507o) from nonmanual and 17 (8507o) from manual social class backgrounds. All these children then received two further home visits, one consisting of a more intensive interview concerning family relationships and parental health and the other a visit from a psychologist who administered a battery of developmental tests. As a result of refusals, the eventual numbers of children in the above groups who received both these follow-up visits were 99 children in the behavior-problem and control groups and 18 in the language-delay group. Nine children from the language-delay group were also in the behaviorproblem group and two were in the control group; thus a total of 205 children received the follow-up visits.

4 302 Stevenson and Richman Developmental Assessment The 205 intensively studied children were given a developmental assessment at home by a psychologist who was unaware of the child's behavioral status but who was told if language delay was suspected. The assessments were given within 1 month of the children's third birthday. The battery of tests and subtests used was as follows: RDLS--Reynell Developmental Language Scales (Reynell, 1969). Subtest: Expressive Scale, a standardized test of productive language ability. The standard scores are presented in terms of standard deviation units, i.e., at any given age the mean score =.00 with 68% of children scoring between and EPVTmEnglish Picture Vocabulary Test (Preschool version) (Brimer & Dunn, 1962). A standardized test of word comprehension. The standard scores are given with a mean of 100 and a standard deviation of 15. ITPAmlllinois Test of Psycholinguistic Abilities (Revised Edition) (Kirk, McCarthy, & Kirk, 1968). Subtest: Auditory Sequential Memory, a standardized test of short-term recall of digits. The results are presented as scale scores with a mean, at a given age, of 36 and a standard deviation of 6. GMDS--Griffiths Mental Development Scales (Extended Scales) (Griffiths, 1970). Subtest: Scale D, Hand/Eye Coordination, a standardized test of the ability to coordinate hand and eye in fine motor movements. The scores are given as quotients with a mean of 100 and a standard deviation of 15. Scale E, Performance, a standardized test of the ability of the child to solve visuospatial problems using bricks and form boards. The score is given as a quotient with a mean of 100 and a standard deviation of 17. Hiskey-Nebraska Test of Learning Aptitude (Hiskey, 1966). Subtest: Memory for Color, a standardized test of the ability to recall sequences of colored sticks. However, since the standardization is not very reliable at the age of 3, the raw scores were used in the present study. At this age the mean raw score obtained in the standardization sample was between 3 and 4. Rating Scales of Child Test Behavior. (Full details are available from the authors.) An unstandardized series of or 5-point rating scales of the child's behavior during the test session. Each dimension of behavior has been classified according to whether it was concerned with behavior that could be considered as a direct (D) or an indirect (I) response to the test material, those classified as a direct response being more likely to affect the scores on tests. The dimensions of test behavior were Test Task Understanding (D), Rapport (I), Guessing (D), Speed of Response (D), Spontaneous Speech (I), Directive Speech (I), Task Orientation (D), Motor Activity (I), Fidgetiness (I), Response Perseveration (D), Need for Tester Praise (I), Need for Parental Contact (I), Habits (I), and Mood (I).

5 Behavior, Language, and Development 303 Neurodevelopmental Score. (Full details are available from authors.) An unstandardized score constructed on the basis of the following items: walking, running, jumping from ground, jumping from box, standing on left/right foot, throwing, kicking, hand-to-hand transfer to objects, threading beads, screwing barrel halves together, use of scissors, folding paper, hearing, and laterality. A simple pass/fail score was made for each of these items and the developmental score obtained by expressing the total number of items failed as a proportion of the number of items attempted. Thus the range of possible scores goes from 0 (no items failed) to 1 (all items failed). The purpose of obtaining this score was to summarize "soft" neurological signs from the separate tests supplemented by specifically requested items, so that an index of neurological development might be produced. Table I. Percentage of Children in the Total Population, Language-Delay Group, and Behavior-Problem Group That Were Rated as Showing Various Behavioral Items Either Frequently or to a Marked Degree Language- Behavior- Total population delay group problem group Behavior items (N = 705) (N = 24) (N = 99) Poor appetite a 46.0 Faddy eater Difficulty in settling at night Waking at night (at least 3 times a week) Sleeping with parents Overactive b 58.6 Poor concentration b 25.2 Dependency ' a 17.2 Attention seeking Tempers Difficult to control c 54.4 Unhappy mood a 18.2 Worries Fears Relations with sibs b 34.5 Relations with peers a 25.3 Soiling (once a week or more) c 25.3 Night wetting (3 nights a week or more) c 47.5 Day wetting (once a week or more) c 30.3 ap <.05, compared with total population. bp <.01, compared with total population. ep <.001, compared with total population.

6 304 Stevenson and Riehman The test-retest reliability of this battery of tests administered under these conditions has previously been established (Stevenson, Note 1). The test-retest reliabilities were: for the GMDS subtests and the RDLS Expressive Language Scale, in the range of.70 to.78; for the EPVT (rtt =.42); for the ITPA Auditory Sequential Memory (rtt =.44); for the Hiskey Nebraska Memory for Color (rtt =.66). The test-retest reliability of the neurodevelopmental score is not known. The ratings of the child's test behavior showed high levels of agreement on the two independently rated test sessions. A disagreement between the two ratings of 2 or more points occurred on more than 807o of occasions for only 3 of the scales: for Rapport (a 5-point scale), Need for Tester Praise (a 3-point scale), and Need for Parental Contact (a 5-point scale). The 14 scales consisted of 5 3-point scales and 9 5-point scales, and therefore these levels of agreement were considered very satisfactory. Final Constitution of the Language-Delay Group Of the 20 children identified by the screening procedure as at risk for language delay, 18 were given developmental assessments (for the remaining 2 parental permission to see the child was not given). All these 18 children were found to show language delay (defined as a language age less than 30 months on the RDLS Expressive Scale); in addition, a further 4 children, all from the behavior problem group, were found to have this degree of delay. Thus the language-delay group finally consisted of 24 children, on 22 of whom developmental assessment data were obtained confirming their language delay. RESULTS The Association Between Behavioral Problems and Language Delay A marked association was found between the presence of language delay and behavior problems. In the total sample of 705 indigenous children, 101 children (14.3~ were found with behavior problems, i.e., with a score of 10+ on the BSQ. Of the 22 children with expressive language delay (defined as a language age less than 30 months), 13 were identified as having behavior problems on the BSQ ( ); the difference in these proportions is highly significant (p <.001). Similarly, of the children with behavior problems had expressive language delay on the screening tests, as compared to of the total

7 Behavior, Language, and Development 305 population; again, this difference in proportions is highly significant (p<.001). Of the four children with specific expressive language delay not associated with general retardation (i.e., language age less than ~ nonverbal mental age and nonverbal mental age more than 88 chronological age), three children had behavior problems; unfortunately the numbers here are too small to draw statistically satisfactory conclusions. Types of Problem Behavior Associated with Language Delay One child with language delay was severely retarded with autistic features; otherwise, there was little difference in the pattern of difficult behavior shown by children with or without language delay. Table I presents the percentages of children in the total population, the languagedelay group and the behavior-problem group that showed various behavioral items either frequently or to a marked degree (i.e., a rating of 2 on the BSQ). It should be noted that the parents of the children with language delay could not report them as showing "worries" since this was dependent on the child's ability to verbalize worries. In general, the frequency of the behavioral items in the language delay group falls midway between those in the total population and behavior problem group. However, the immaturity of children in the language-delay group is shown by high rates of failure to achieve sphincter control. Problems in social relationships (dependency, relationship with sibs, and relationships with peers) were significantly more frequent in the language-delay group than in the total population, as were difficulties with parental control, unhappy moods, poor appetite, overactivity, and concentration. More of the behavior problems in the language-delay group were likely to be rated as of moderate or marked severity compared with the population as a whole. Of the 52 children with moderate/marked behavior problems, 12 had language delay (23.0%) compared to an estimated rate of language delay of 4.3~ in those with mild behavior problems (p<.001). Developmental Test Results Comparing Children with Behavior Problems and Their Controls The data in Table II summarize the comparisons between the children with behavior problems and their controls. The number of children contributing a resur to each test varies since only those tests with all items completed are included. These results show that for all tests except the Per-

8 Table II. Comparison of the Scores on Psychodevelopmental Testing of Children with Behavior Problems and Controls Test N Mean SD N Mean SD t df p English Picture Vocabulary Test : <.01 standard score RDLS, Expressive Language Scale <.01 standard score ITPA, Auditory Sequential <.01 Memory scale score Hiskey-Nebraska Memory for <.02 Color score GMDS, Scale D <.01 Hand/Eye Coordination QD GMDS, Scale E n.s. Performance QE Neurodevelopmental score <,01 Behavior-problem group Control group

9 Table III. Comparison of Scores on Psychodevelopmental Testing of Children with and without Behavior Problems, Excluding Children with Language Delay Test N Mean SD N Mean SD t df p O EPVT standard score <.05 RDLS, Expressive Scale standard score <.01 ITPA, Auditory Sequential Memory scale score <.01 Hiskey-Nebraska Memory for Color score <.05 GMDS, Scale D QD <.05 GMDS, Scale E QE n,s. Neurodevelopmental score n,s. la m Behavior problem Controls

10 308 Stevenson and Richman formance Scale of the GMDS, the group with behavior problems performed significantly worse than those children without behavior problems. However, in all cases where standard scores were used, both groups performed at or above average for their age. As has been shown in the previous section, the group of children with behavior problems contains significantly more children with language delay. Accordingly, in Table III the mean scores on the tests are compared for the group of children with and without behavior problems who do not fall into the language-delayed category. These results show that there are significant differences between the two groups, even when the children with language delay are excluded, and that these differences lie mainly in the verbal tests. Developmental Test Results of Children with Language Delay When the group of children with language delay but no behavior problems is compared with the group who have language delay and behavior problems, no significant differences are found between them (Table IV), though the numbers are small. However, it can be seen from Table IV that although the children with language delay and behavior problems score lower on the tests of language development, there is a consistent but statistically nonsignificant trend for the children with language delay and with no behavior problems to score lower on the nonverbal tests. Analyses of covariance were therefore carried out to test for significant differences between the groups on nonverbal scores (GMDS Scale D and Scale E, and neurodevelopmental score) when EPVT and RDLS Expressive Scale raw scores were controlled for as covariates. Using this procedure, no significant differences were found between the language-delay-only and language-delay and behavior-problem groups. Correlations Between the Tests Product-moment correlations among the five variables for which the most complete data were available are presented in Table V. These are based on the pooled data of all subjects in the sample of 205 children intensively investigated. It was found that the psychodevelopmental tests (i.e., excluding behavior score) correlate significantly with each other (p<.01). First-order partial correlation coefficients were calculated controlling for each of the other variables in Table V in turn; these coefficients are a measure of the association between two variables when their association with a third variable has been taken into account. All these first-order

11 Table IV. Comparison of Scores on Psychodevelopmental Testing of Children with Language Delay with and without Behavior Problems e~ e~ No behavior problems with language delay Behavior problems and language delay Test N Mean SD N Mean SD t df p EPVT standard score 8 85, n.s. RDLS Expressive Scale standard score n.s. GMDS Scale D QD n.s. GMDS Scale E 8 84, n,s. Neurodevelopmental score 9, n.s,

12 310 Stevenson and Richman Table V. Product-Moment Correlation Coefficients Between the Five Main Variables for the Total Sample (N = 205) a BSQ b RDLS Expressive Scale c 511 c -519 c 3. GMDS Scale D c -650 c 4. GMDS Scale E c 5. Neurodevelopmental score aall decimal places have been omitted. bp <.05. Cp <.01. partial correlations are still significant (p<.01), which means that the high levels of correlation seen in Table V are not merely a result of a common association with a particular variable that is influencing each of the others. However, it can be seen in Table V that the BSQ correlates at a significant level with only the RDLS Expressive Scale standard score (r = -.164, p<.05). This correlation falls below significance when the firstorder partial correlation, with neurodevelopmental score controlled, is calculated (r = , p >.05). Ratings of the Children "s Behavior During Testing As described above, the children's behavior during testing was rated on 14 dimensions of behavior. These data have been previously used to provide some validation of the BSQ as an instrument for identifying children with abnormal behavior (Richman et al., 1975). Table VI presents the distributions of the ratings for the control and behavior-problem groups on those dimensions that did show a significant difference between the two groups. Of the five scales that are a direct response to the test materials (Test Task Understanding, Guessing, Speed of Response, Task Orientation, and Response Perseveration) only Guessing did not show a significant difference between the control and behaviorproblem groups. Of the remaining nine scales that were considered to be only an indirect response to the test material (Rapport, Spontaneous Speech, Directive Speech, Motor Activity, Fidgetiness, Need for Tester Praise, Need for Parental Contact, Habits, and Mood), only in the case of Rapport was there a significant difference between the two groups. Rating of Clarity of Speech During Testing A rating was made on a 3-point scale of the comprehensibility of the child's speech. All but two of the children with language delay were rated as

13 Behavior, Language, and Development 311 Table VI. Distribution of Ratings of Test Behavior for the 99 Control and 99 Behavior- Problem Children on Those Rating Scales That Showed Significant Differences Between the Two Groups Rating b High Low Rating scale a Group x 2 df p Test Task Understanding (D) Control <.05 Behavior Rapport (I) Control <.01 Behavior Speed of Response (D) Control <.02 Behavior Task Orientation (D) Control <.02 Behavior Response Perseveration (D) Control <.01 Behavior a I = indite ctly concerned with test materials; D = directly concerned with test materials. btest Task Understanding and Response Perseveration were rated on 3-point scales. Other categories shown were rated on 5-point scales. having "very unclear" speech. This mainly resulted from articulation errors in the speech of these children. Significantly more of the children with behavior problems (58%) than of the control children (42%) were rated as having "slightly unclear" or "very unclear" speech (X 2 = 9.14, df = 2, p<.02). DISCUSSION There are consistent findings throughout the data presented that show associations between behavior problems and language development in 3-year-old children. The prevalence of behavior problems in the total population was found to be 14.3% and in children with language delay to be 59.1%. Similarly, the rates of language delay in the total population and in children with behavior problems were 3.1% and 12.9%, respectively. The children with behavior problems scored less well than controls on expressive language and language comprehension even when those children with language delay were excluded from both groups. Although the behaviorproblem group was performing significantly less well on some of the nonverbal measures as well, when the children with language delay were excluded from the groups only the Hand/Eye Coordination Scale of the Griffiths test still showed a significant difference. The results of the ratings of the children's behavior during testing might suggest that the differences in test scores observed between children

14 312 Stevenson and Richman with and without behavior problems could have resulted from a difference in behavior while being tested rather than from real differences in ability. However, differences were not observed on all tests, as might be expected if the test results were being produced by the response of the children to the test situation. Moreover, it was tests of language development that most consistently showed differences between groups, and no difference was recorded in the behavior-problem children's use of direct and spontaneous speech during the test session. These are the scales on which the greatest differences would have been expected if the behavior-problem children's test results were adversely affected by their behavior in the test situation. The findings based on comparisons of group means are supported by the correlational analysis. The behavior score was significantly correlated only with the Reynell Expressive Scale Standard Score and not with any of the nonverbal measures. It can be concluded from all these data that the development of language and the presence of behavior problems are related in general and the association is particularly strong when the children with language delay are investigated. It is not possible, on the basis of the associations demonstrated here, to determine whether the joint occurrence of behavior and language problems is due to the effect of communication deficits on the development of behavior or the effect of disturbed behavior on the acquisition of expressive language. A third possibility is that in doubly handicapped children there is a common cause, for example, environmental stress or maternal depression, that may be producing these two disabilities. These factors have been investigated in two other reports. Richman (1977) has shown a marked association between behavior problems and social and family factors, and it has also been shown that children with language delay come from particularly adverse social conditions (Richman & Stevenson, 1977). REFERENCE NOTE 1. Stevenson, J. E. The test-retest reliability of a battery of developmental tests and a rating scale of test behaviour for use with three year old children. Unpublished manuscript, REFERENCES Bartak, L., Rutter, M., & Cox, A. A comparative study of infantile autism and specific receptive language disorder: I. The children. British Journal of Psychiatry, 1975, 126, Brimer, M. A., & Dunn, L. M. Manual for the English Picture Vocabulary Tests. Bristol: Educational Evaluation Enterprises, 1962.

15 Behavior, Language, and Development 313 Chess, S., & Rosenberg, M. Clinical differentiation between children with initial language complaints. Journal of Autism and Childhood Schizophrenia, 1974, 4, Friedlander, B. Z., Wetstone, H. S., & McPeek, D. L. Systematic assessment of selective language listening deficit in emotionally disturbed children. Journal of Child Psychology and Psychiatry, 1974, 15, Griffiths, R. The abilities of young children. London: Child Development Research Centre, Hermelin, B., & O'Connor, N. Psychological experiments with autistic children. Oxford: Pergamon, Hiskey, M. S. Hiskey-Nebraska Test of Learning Aptitude. Lincoln, Nebraska: Union College Press, Ingram, T. T. S. Specific developmental disorders of speech in childhood. Brain, 1959, 82, Kirk, S. A., McCarthy, J. J., & Kirk, W. D. Illinois Test of Psycholinguistic Abilities (Rev. ed.). Urbana: University of Illinois Press, Reynell, J. K. Reynell Developmental Language Scales. Experimental edition. Windsor: N.F.E.R. Publishing Co., Richman, N. Behaviour problems in pre-school children: Family and social factors. British Journal of Psychiatry, 1977, 131, Richman, N., & Graham, P. J. A behavioural screening questionnaire for use with three year old children. Journal of Child Psychology and Psychiatry, 1971, 12, Richman, N., & Stevenson, J. Language delay in 3-year old children: Family and social factors. Acta Paediatrica Belgica, 1977, 30, Richman, N., Stevenson, J. E., & Graham, P. J. Prevalence of behaviour problems in three year old children: An epidemiological study in a London borough. Journal of Child Psychology and Psychiatry, 1975, 16, Richman, N., & Tupting, H. A computerised register of families with children under five in a London borough. Health Trends, 1974, 6, Rutter, M. L., Tizard, J., & Whitmore, K. (Eds.). Education, health and behaviour. London: Longman, Stevenson, J. E., & Richman, N. The prevalence of language delay in a population of three year old children and its association with general retardation. Developmental Medicine and ChiM Neurology, 1976, 18,